255 lines
156 KiB
HTML
255 lines
156 KiB
HTML
<!DOCTYPE html>
|
||
<html lang="zh-CN" dir="ltr">
|
||
<head>
|
||
<meta charset="utf-8">
|
||
<meta name="viewport" content="width=device-width,initial-scale=1">
|
||
<title>循环结构 | 查尔斯的知识库</title>
|
||
<meta name="description" content="个人技术知识库，记录 & 分享个人碎片化、结构化、体系化的技术知识内容。">
|
||
<meta name="generator" content="VitePress v1.0.0-rc.31">
|
||
<link rel="preload stylesheet" href="/assets/style.-TyODVlN.css" as="style">
|
||
|
||
<script type="module" src="/assets/app.wVULdALl.js"></script>
|
||
<link rel="preload" href="/assets/inter-roman-latin.bvIUbFQP.woff2" as="font" type="font/woff2" crossorigin="">
|
||
<link rel="modulepreload" href="/assets/chunks/framework.FVQzxbLi.js">
|
||
<link rel="modulepreload" href="/assets/chunks/theme.H88Ua6lx.js">
|
||
<link rel="modulepreload" href="/assets/chunks/md5.RtphNWHi.js">
|
||
<link rel="modulepreload" href="/assets/chunks/use-popup-manager.-j2MED7j.js">
|
||
<link rel="modulepreload" href="/assets/chunks/ArticleMetadata.Sb1DYAHo.js">
|
||
<link rel="modulepreload" href="/assets/courses_java_01-Java语法入门_10-循环结构.md.z73Bcwe8.lean.js">
|
||
<link rel="icon" href="/favicon.ico">
|
||
<meta name="author" content="Charles7c">
|
||
<meta name="keywords" content="查尔斯的知识库, 知识库, 博客, Charles7c">
|
||
<meta name="HandheldFriendly" content="True">
|
||
<meta name="MobileOptimized" content="320">
|
||
<meta name="theme-color" content="#3c8772">
|
||
<meta property="og:type" content="website">
|
||
<meta property="og:locale" content="zh_CN">
|
||
<meta property="og:title" content="查尔斯的知识库">
|
||
<meta property="og:description" content="个人技术知识库，记录 & 分享个人碎片化、结构化、体系化的技术知识内容。">
|
||
<meta property="og:site" content="https://blog.charles7c.top">
|
||
<meta property="og:site_name" content="查尔斯的知识库">
|
||
<meta property="og:image" content="https://blog.charles7c.top/logo.jpg">
|
||
<script>var _hmt=_hmt||[];(function(){var e=document.createElement("script");e.src="https://hm.baidu.com/hm.js?53af4b1a12fbe40810ca7ad39f8db9c7";var t=document.getElementsByTagName("script")[0];t.parentNode.insertBefore(e,t)})();</script>
|
||
<script id="check-dark-mode">(()=>{const e=localStorage.getItem("vitepress-theme-appearance")||"auto",a=window.matchMedia("(prefers-color-scheme: dark)").matches;(!e||e==="auto"?a:e==="dark")&&document.documentElement.classList.add("dark")})();</script>
|
||
<script id="check-mac-os">document.documentElement.classList.toggle("mac",/Mac|iPhone|iPod|iPad/i.test(navigator.platform));</script>
|
||
</head>
|
||
<body>
|
||
<div id="app"><div class="Layout" data-v-03322d68><!--[--><!--]--><!--[--><span tabindex="-1" data-v-c4918e4e></span><a href="#VPContent" class="VPSkipLink visually-hidden" data-v-c4918e4e> Skip to content </a><!--]--><!----><header class="VPNav" data-v-03322d68 data-v-629c70bd><div class="VPNavBar has-sidebar" data-v-629c70bd data-v-1d72176a><div class="container" data-v-1d72176a><div class="title" data-v-1d72176a><div class="VPNavBarTitle has-sidebar" data-v-1d72176a data-v-21327bbd><a class="title" href="/" data-v-21327bbd><!--[--><!--]--><!--[--><img class="VPImage logo" src="/logo.png" alt data-v-d7b35c78><!--]--><!--[-->查尔斯的知识库<!--]--><!--[--><!--]--></a></div></div><div class="content" data-v-1d72176a><div class="curtain" data-v-1d72176a></div><div class="content-body" data-v-1d72176a><!--[--><!--]--><div class="VPNavBarSearch search" data-v-1d72176a><!--[--><!----><div id="docsearch"><button type="button" class="DocSearch DocSearch-Button" aria-label="搜索文档"><span class="DocSearch-Button-Container"><svg class="DocSearch-Search-Icon" width="20" height="20" viewBox="0 0 20 20" aria-label="search icon"><path d="M14.386 14.386l4.0877 4.0877-4.0877-4.0877c-2.9418 2.9419-7.7115 2.9419-10.6533 0-2.9419-2.9418-2.9419-7.7115 0-10.6533 2.9418-2.9419 7.7115-2.9419 10.6533 0 2.9419 2.9418 2.9419 7.7115 0 10.6533z" stroke="currentColor" fill="none" fill-rule="evenodd" stroke-linecap="round" stroke-linejoin="round"></path></svg><span class="DocSearch-Button-Placeholder">搜索文档</span></span><span class="DocSearch-Button-Keys"><kbd class="DocSearch-Button-Key"></kbd><kbd class="DocSearch-Button-Key">K</kbd></span></button></div><!--]--></div><nav aria-labelledby="main-nav-aria-label" class="VPNavBarMenu menu" data-v-1d72176a data-v-a12edbe3><span id="main-nav-aria-label" class="visually-hidden" data-v-a12edbe3>Main Navigation</span><!--[--><!--[--><div class="VPFlyout VPNavBarMenuGroup" data-v-a12edbe3 data-v-f18e2dbf><button type="button" class="button" aria-haspopup="true" aria-expanded="false" data-v-f18e2dbf><span class="text" data-v-f18e2dbf><!----><span data-v-f18e2dbf>我的分类</span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="text-icon" data-v-f18e2dbf><path d="M12,16c-0.3,0-0.5-0.1-0.7-0.3l-6-6c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l5.3,5.3l5.3-5.3c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-6,6C12.5,15.9,12.3,16,12,16z"></path></svg></span></button><div class="menu" data-v-f18e2dbf><div class="VPMenu" data-v-f18e2dbf data-v-8a7fe2f1><div class="items" data-v-8a7fe2f1><!--[--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/categories/issues/index" data-v-cf652a9b><!--[-->Bug万象集<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/categories/fragments/index" data-v-cf652a9b><!--[-->"杂碎"逆袭史<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/categories/tools/index" data-v-cf652a9b><!--[-->工具四海谈<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/categories/solutions/index" data-v-cf652a9b><!--[-->方案春秋志<!--]--></a></div><!--]--><!--]--></div><!--[--><!--]--></div></div></div><!--]--><!--[--><div class="VPFlyout VPNavBarMenuGroup active" data-v-a12edbe3 data-v-f18e2dbf><button type="button" class="button" aria-haspopup="true" aria-expanded="false" data-v-f18e2dbf><span class="text" data-v-f18e2dbf><!----><span data-v-f18e2dbf>我的小册</span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="text-icon" data-v-f18e2dbf><path d="M12,16c-0.3,0-0.5-0.1-0.7-0.3l-6-6c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l5.3,5.3l5.3-5.3c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-6,6C12.5,15.9,12.3,16,12,16z"></path></svg></span></button><div class="menu" data-v-f18e2dbf><div class="VPMenu" data-v-f18e2dbf data-v-8a7fe2f1><div class="items" data-v-8a7fe2f1><!--[--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link active" href="/courses/java/index" data-v-cf652a9b><!--[-->Java基础快速入门<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/courses/mysql/index" data-v-cf652a9b><!--[-->MySQL快速入门<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/courses/mybatis/index" data-v-cf652a9b><!--[-->MyBatis快速入门<!--]--></a></div><!--]--><!--]--></div><!--[--><!--]--></div></div></div><!--]--><!--[--><a class="VPLink link VPNavBarMenuLink" href="/tags" tabindex="0" data-v-a12edbe3 data-v-bc587c79><!--[--><span data-v-bc587c79>我的标签</span><!--]--></a><!--]--><!--[--><a class="VPLink link VPNavBarMenuLink" href="/archives" tabindex="0" data-v-a12edbe3 data-v-bc587c79><!--[--><span data-v-bc587c79>我的归档</span><!--]--></a><!--]--><!--[--><div class="VPFlyout VPNavBarMenuGroup" data-v-a12edbe3 data-v-f18e2dbf><button type="button" class="button" aria-haspopup="true" aria-expanded="false" data-v-f18e2dbf><span class="text" data-v-f18e2dbf><!----><span data-v-f18e2dbf>关于</span><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="text-icon" data-v-f18e2dbf><path d="M12,16c-0.3,0-0.5-0.1-0.7-0.3l-6-6c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l5.3,5.3l5.3-5.3c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-6,6C12.5,15.9,12.3,16,12,16z"></path></svg></span></button><div class="menu" data-v-f18e2dbf><div class="VPMenu" data-v-f18e2dbf data-v-8a7fe2f1><div class="items" data-v-8a7fe2f1><!--[--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/about/index" data-v-cf652a9b><!--[-->关于知识库<!--]--></a></div><!--]--><!--[--><div class="VPMenuLink" data-v-8a7fe2f1 data-v-cf652a9b><a class="VPLink link" href="/about/me" data-v-cf652a9b><!--[-->关于我<!--]--></a></div><!--]--><!--]--></div><!--[--><!--]--></div></div></div><!--]--><!--]--></nav><!----><div class="VPNavBarAppearance appearance" data-v-1d72176a data-v-c2c90abb><button class="VPSwitch VPSwitchAppearance" type="button" role="switch" title="Switch to dark theme" aria-checked="false" data-v-c2c90abb data-v-1502017d data-v-54e1997a><span class="check" data-v-54e1997a><span class="icon" data-v-54e1997a><!--[--><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="sun" data-v-1502017d><path d="M12,18c-3.3,0-6-2.7-6-6s2.7-6,6-6s6,2.7,6,6S15.3,18,12,18zM12,8c-2.2,0-4,1.8-4,4c0,2.2,1.8,4,4,4c2.2,0,4-1.8,4-4C16,9.8,14.2,8,12,8z"></path><path d="M12,4c-0.6,0-1-0.4-1-1V1c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,3.6,12.6,4,12,4z"></path><path d="M12,24c-0.6,0-1-0.4-1-1v-2c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,23.6,12.6,24,12,24z"></path><path d="M5.6,6.6c-0.3,0-0.5-0.1-0.7-0.3L3.5,4.9c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C6.2,6.5,5.9,6.6,5.6,6.6z"></path><path d="M19.8,20.8c-0.3,0-0.5-0.1-0.7-0.3l-1.4-1.4c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C20.3,20.7,20,20.8,19.8,20.8z"></path><path d="M3,13H1c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S3.6,13,3,13z"></path><path d="M23,13h-2c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S23.6,13,23,13z"></path><path d="M4.2,20.8c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C4.7,20.7,4.5,20.8,4.2,20.8z"></path><path d="M18.4,6.6c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C18.9,6.5,18.6,6.6,18.4,6.6z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="moon" data-v-1502017d><path d="M12.1,22c-0.3,0-0.6,0-0.9,0c-5.5-0.5-9.5-5.4-9-10.9c0.4-4.8,4.2-8.6,9-9c0.4,0,0.8,0.2,1,0.5c0.2,0.3,0.2,0.8-0.1,1.1c-2,2.7-1.4,6.4,1.3,8.4c2.1,1.6,5,1.6,7.1,0c0.3-0.2,0.7-0.3,1.1-0.1c0.3,0.2,0.5,0.6,0.5,1c-0.2,2.7-1.5,5.1-3.6,6.8C16.6,21.2,14.4,22,12.1,22zM9.3,4.4c-2.9,1-5,3.6-5.2,6.8c-0.4,4.4,2.8,8.3,7.2,8.7c2.1,0.2,4.2-0.4,5.8-1.8c1.1-0.9,1.9-2.1,2.4-3.4c-2.5,0.9-5.3,0.5-7.5-1.1C9.2,11.4,8.1,7.7,9.3,4.4z"></path></svg><!--]--></span></span></button></div><div class="VPSocialLinks VPNavBarSocialLinks social-links" data-v-1d72176a data-v-804ae77e data-v-f57dd261><!--[--><a class="VPSocialLink no-icon" href="https://github.com/Charles7c/charles7c.github.io" aria-label="github" target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>GitHub</title><path d="M12 .297c-6.63 0-12 5.373-12 12 0 5.303 3.438 9.8 8.205 11.385.6.113.82-.258.82-.577 0-.285-.01-1.04-.015-2.04-3.338.724-4.042-1.61-4.042-1.61C4.422 18.07 3.633 17.7 3.633 17.7c-1.087-.744.084-.729.084-.729 1.205.084 1.838 1.236 1.838 1.236 1.07 1.835 2.809 1.305 3.495.998.108-.776.417-1.305.76-1.605-2.665-.3-5.466-1.332-5.466-5.93 0-1.31.465-2.38 1.235-3.22-.135-.303-.54-1.523.105-3.176 0 0 1.005-.322 3.3 1.23.96-.267 1.98-.399 3-.405 1.02.006 2.04.138 3 .405 2.28-1.552 3.285-1.23 3.285-1.23.645 1.653.24 2.873.12 3.176.765.84 1.23 1.91 1.23 3.22 0 4.61-2.805 5.625-5.475 5.92.42.36.81 1.096.81 2.22 0 1.606-.015 2.896-.015 3.286 0 .315.21.69.825.57C20.565 22.092 24 17.592 24 12.297c0-6.627-5.373-12-12-12"/></svg></a><a class="VPSocialLink no-icon" href="https://gitee.com/Charles7c/charles7c" aria-label target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>码云</title><path d="M11.984 0A12 12 0 0 0 0 12a12 12 0 0 0 12 12 12 12 0 0 0 12-12A12 12 0 0 0 12 0a12 12 0 0 0-.016 0zm6.09 5.333c.328 0 .593.266.592.593v1.482a.594.594 0 0 1-.593.592H9.777c-.982 0-1.778.796-1.778 1.778v5.63c0 .327.266.592.593.592h5.63c.982 0 1.778-.796 1.778-1.778v-.296a.593.593 0 0 0-.592-.593h-4.15a.592.592 0 0 1-.592-.592v-1.482a.593.593 0 0 1 .593-.592h6.815c.327 0 .593.265.593.592v3.408a4 4 0 0 1-4 4H5.926a.593.593 0 0 1-.593-.593V9.778a4.444 4.444 0 0 1 4.445-4.444h8.296Z"/></svg></a><a class="VPSocialLink no-icon" href="https://cnadmin.charles7c.top/" aria-label target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg width="33" height="33" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 174.8 204">
|
||
<title>ContiNew Admin</title>
|
||
<path fill="#307AF2" d="M86.7,0l88,51v.2l-16.3,9.4v-.2L86.7,18.9Zm71.8,143.5,16.3,9.4v.2L86.8,204h0l-16.3-9.4,16.3-9.4h0l71.7-41.5v-.2Z"/>
|
||
<path fill="#12D2AC" d="M16.3,143.5v.2L58,167.8l-16.3,9.4L0,153.1v-.2Z"/>
|
||
<path fill="#12D2AC" d="M104.1,93,15.9,143.8l-.2-.1V124.9l.2.1L87.7,83.6,104.1,93Z"/>
|
||
<path fill="#0057FE" d="M88.1,0,.1,51v.2l16.3,9.4v-.2L88.1,18.9Z"/>
|
||
<path fill="#307AF2" d="M.1,50.9.2,152.6l.2.1,16.3-9.4-.2-.1-.1-82.9L.1,50.9Z"/>
|
||
<path fill="#0057FE" d="M174.7,50.9l-.1,101.7-.2.1-16.3-9.4.2-.1.1-82.9Z"/>
|
||
<path fill="#12D2AC" d="M41.7,158.5l16.1,9.4,100.6-58.7V90.4Z"/>
|
||
</svg></a><!--]--></div><div class="VPFlyout VPNavBarExtra extra" data-v-1d72176a data-v-3893c6ae data-v-f18e2dbf><button type="button" class="button" aria-haspopup="true" aria-expanded="false" aria-label="extra navigation" data-v-f18e2dbf><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="icon" data-v-f18e2dbf><circle cx="12" cy="12" r="2"></circle><circle cx="19" cy="12" r="2"></circle><circle cx="5" cy="12" r="2"></circle></svg></button><div class="menu" data-v-f18e2dbf><div class="VPMenu" data-v-f18e2dbf data-v-8a7fe2f1><!----><!--[--><!--[--><!----><div class="group" data-v-3893c6ae><div class="item appearance" data-v-3893c6ae><p class="label" data-v-3893c6ae>切换日光/暗黑模式</p><div class="appearance-action" data-v-3893c6ae><button class="VPSwitch VPSwitchAppearance" type="button" role="switch" title="Switch to dark theme" aria-checked="false" data-v-3893c6ae data-v-1502017d data-v-54e1997a><span class="check" data-v-54e1997a><span class="icon" data-v-54e1997a><!--[--><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="sun" data-v-1502017d><path d="M12,18c-3.3,0-6-2.7-6-6s2.7-6,6-6s6,2.7,6,6S15.3,18,12,18zM12,8c-2.2,0-4,1.8-4,4c0,2.2,1.8,4,4,4c2.2,0,4-1.8,4-4C16,9.8,14.2,8,12,8z"></path><path d="M12,4c-0.6,0-1-0.4-1-1V1c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,3.6,12.6,4,12,4z"></path><path d="M12,24c-0.6,0-1-0.4-1-1v-2c0-0.6,0.4-1,1-1s1,0.4,1,1v2C13,23.6,12.6,24,12,24z"></path><path d="M5.6,6.6c-0.3,0-0.5-0.1-0.7-0.3L3.5,4.9c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C6.2,6.5,5.9,6.6,5.6,6.6z"></path><path d="M19.8,20.8c-0.3,0-0.5-0.1-0.7-0.3l-1.4-1.4c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l1.4,1.4c0.4,0.4,0.4,1,0,1.4C20.3,20.7,20,20.8,19.8,20.8z"></path><path d="M3,13H1c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S3.6,13,3,13z"></path><path d="M23,13h-2c-0.6,0-1-0.4-1-1s0.4-1,1-1h2c0.6,0,1,0.4,1,1S23.6,13,23,13z"></path><path d="M4.2,20.8c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C4.7,20.7,4.5,20.8,4.2,20.8z"></path><path d="M18.4,6.6c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l1.4-1.4c0.4-0.4,1-0.4,1.4,0s0.4,1,0,1.4l-1.4,1.4C18.9,6.5,18.6,6.6,18.4,6.6z"></path></svg><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="moon" data-v-1502017d><path d="M12.1,22c-0.3,0-0.6,0-0.9,0c-5.5-0.5-9.5-5.4-9-10.9c0.4-4.8,4.2-8.6,9-9c0.4,0,0.8,0.2,1,0.5c0.2,0.3,0.2,0.8-0.1,1.1c-2,2.7-1.4,6.4,1.3,8.4c2.1,1.6,5,1.6,7.1,0c0.3-0.2,0.7-0.3,1.1-0.1c0.3,0.2,0.5,0.6,0.5,1c-0.2,2.7-1.5,5.1-3.6,6.8C16.6,21.2,14.4,22,12.1,22zM9.3,4.4c-2.9,1-5,3.6-5.2,6.8c-0.4,4.4,2.8,8.3,7.2,8.7c2.1,0.2,4.2-0.4,5.8-1.8c1.1-0.9,1.9-2.1,2.4-3.4c-2.5,0.9-5.3,0.5-7.5-1.1C9.2,11.4,8.1,7.7,9.3,4.4z"></path></svg><!--]--></span></span></button></div></div></div><div class="group" data-v-3893c6ae><div class="item social-links" data-v-3893c6ae><div class="VPSocialLinks social-links-list" data-v-3893c6ae data-v-f57dd261><!--[--><a class="VPSocialLink no-icon" href="https://github.com/Charles7c/charles7c.github.io" aria-label="github" target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>GitHub</title><path d="M12 .297c-6.63 0-12 5.373-12 12 0 5.303 3.438 9.8 8.205 11.385.6.113.82-.258.82-.577 0-.285-.01-1.04-.015-2.04-3.338.724-4.042-1.61-4.042-1.61C4.422 18.07 3.633 17.7 3.633 17.7c-1.087-.744.084-.729.084-.729 1.205.084 1.838 1.236 1.838 1.236 1.07 1.835 2.809 1.305 3.495.998.108-.776.417-1.305.76-1.605-2.665-.3-5.466-1.332-5.466-5.93 0-1.31.465-2.38 1.235-3.22-.135-.303-.54-1.523.105-3.176 0 0 1.005-.322 3.3 1.23.96-.267 1.98-.399 3-.405 1.02.006 2.04.138 3 .405 2.28-1.552 3.285-1.23 3.285-1.23.645 1.653.24 2.873.12 3.176.765.84 1.23 1.91 1.23 3.22 0 4.61-2.805 5.625-5.475 5.92.42.36.81 1.096.81 2.22 0 1.606-.015 2.896-.015 3.286 0 .315.21.69.825.57C20.565 22.092 24 17.592 24 12.297c0-6.627-5.373-12-12-12"/></svg></a><a class="VPSocialLink no-icon" href="https://gitee.com/Charles7c/charles7c" aria-label target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>码云</title><path d="M11.984 0A12 12 0 0 0 0 12a12 12 0 0 0 12 12 12 12 0 0 0 12-12A12 12 0 0 0 12 0a12 12 0 0 0-.016 0zm6.09 5.333c.328 0 .593.266.592.593v1.482a.594.594 0 0 1-.593.592H9.777c-.982 0-1.778.796-1.778 1.778v5.63c0 .327.266.592.593.592h5.63c.982 0 1.778-.796 1.778-1.778v-.296a.593.593 0 0 0-.592-.593h-4.15a.592.592 0 0 1-.592-.592v-1.482a.593.593 0 0 1 .593-.592h6.815c.327 0 .593.265.593.592v3.408a4 4 0 0 1-4 4H5.926a.593.593 0 0 1-.593-.593V9.778a4.444 4.444 0 0 1 4.445-4.444h8.296Z"/></svg></a><a class="VPSocialLink no-icon" href="https://cnadmin.charles7c.top/" aria-label target="_blank" rel="noopener" data-v-f57dd261 data-v-19217157><svg width="33" height="33" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 174.8 204">
|
||
<title>ContiNew Admin</title>
|
||
<path fill="#307AF2" d="M86.7,0l88,51v.2l-16.3,9.4v-.2L86.7,18.9Zm71.8,143.5,16.3,9.4v.2L86.8,204h0l-16.3-9.4,16.3-9.4h0l71.7-41.5v-.2Z"/>
|
||
<path fill="#12D2AC" d="M16.3,143.5v.2L58,167.8l-16.3,9.4L0,153.1v-.2Z"/>
|
||
<path fill="#12D2AC" d="M104.1,93,15.9,143.8l-.2-.1V124.9l.2.1L87.7,83.6,104.1,93Z"/>
|
||
<path fill="#0057FE" d="M88.1,0,.1,51v.2l16.3,9.4v-.2L88.1,18.9Z"/>
|
||
<path fill="#307AF2" d="M.1,50.9.2,152.6l.2.1,16.3-9.4-.2-.1-.1-82.9L.1,50.9Z"/>
|
||
<path fill="#0057FE" d="M174.7,50.9l-.1,101.7-.2.1-16.3-9.4.2-.1.1-82.9Z"/>
|
||
<path fill="#12D2AC" d="M41.7,158.5l16.1,9.4,100.6-58.7V90.4Z"/>
|
||
</svg></a><!--]--></div></div></div><!--]--><!--]--></div></div></div><!--[--><!--]--><button type="button" class="VPNavBarHamburger hamburger" aria-label="mobile navigation" aria-expanded="false" aria-controls="VPNavScreen" data-v-1d72176a data-v-a6ca9ab6><span class="container" data-v-a6ca9ab6><span class="top" data-v-a6ca9ab6></span><span class="middle" data-v-a6ca9ab6></span><span class="bottom" data-v-a6ca9ab6></span></span></button></div></div></div></div><!----></header><div class="VPLocalNav reached-top" data-v-03322d68 data-v-b9e3214b><button class="menu" aria-expanded="false" aria-controls="VPSidebarNav" data-v-b9e3214b><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="menu-icon" data-v-b9e3214b><path d="M17,11H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h14c0.6,0,1,0.4,1,1S17.6,11,17,11z"></path><path d="M21,7H3C2.4,7,2,6.6,2,6s0.4-1,1-1h18c0.6,0,1,0.4,1,1S21.6,7,21,7z"></path><path d="M21,15H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h18c0.6,0,1,0.4,1,1S21.6,15,21,15z"></path><path d="M17,19H3c-0.6,0-1-0.4-1-1s0.4-1,1-1h14c0.6,0,1,0.4,1,1S17.6,19,17,19z"></path></svg><span class="menu-text" data-v-b9e3214b>文章</span></button><div class="VPLocalNavOutlineDropdown" style="--vp-vh:0px;" data-v-b9e3214b data-v-06057024><button data-v-06057024>返回顶部</button><!----></div></div><aside class="VPSidebar" data-v-03322d68 data-v-802ad7d8><div class="curtain" data-v-802ad7d8></div><nav class="nav" id="VPSidebarNav" aria-labelledby="sidebar-aria-label" tabindex="-1" data-v-802ad7d8><span class="visually-hidden" id="sidebar-aria-label" data-v-802ad7d8> Sidebar Navigation </span><!--[--><!--]--><!--[--><div class="group" data-v-802ad7d8><section class="VPSidebarItem level-0 collapsible has-active" data-v-802ad7d8 data-v-95d837d1><div class="item" role="button" tabindex="0" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><h2 class="text" data-v-95d837d1>Java语法入门 (14篇)</h2><div class="caret" role="button" aria-label="toggle section" tabindex="0" data-v-95d837d1><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="caret-icon" data-v-95d837d1><path d="M9,19c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l5.3-5.3L8.3,6.7c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l6,6c0.4,0.4,0.4,1,0,1.4l-6,6C9.5,18.9,9.3,19,9,19z"></path></svg></div></div><div class="items" data-v-95d837d1><!--[--><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/01-%E5%BC%80%E5%8F%91%E7%8E%AF%E5%A2%83%E6%90%AD%E5%BB%BA" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-red mr-[6px]" style="font-weight: 550; display: inline-block;">1</div>开发环境搭建</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/02-%E7%AC%AC%E4%B8%80%E4%B8%AAJava%E7%A8%8B%E5%BA%8F" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-orange mr-[6px]" style="font-weight: 550; display: inline-block;">2</div>第一个Java程序</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/03-%E5%88%9D%E8%AF%86Eclipse" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-yellow mr-[6px]" style="font-weight: 550; display: inline-block;">3</div>初识Eclipse</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/04-%E7%A8%8B%E5%BA%8F%E5%92%8C%E8%AE%A1%E7%AE%97%E6%9C%BA%E7%9A%84%E9%82%A3%E7%82%B9%E4%BA%8B%E5%84%BF" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">4</div>程序和计算机的那点事儿</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/05-%E5%8F%98%E9%87%8F%E5%92%8C%E5%B8%B8%E9%87%8F" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">5</div>变量和常量</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/06-%E5%B8%B8%E7%94%A8%E7%9A%84%E8%BF%90%E7%AE%97%E7%AC%A6" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">6</div>常用的运算符</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/07-%E6%8E%A7%E5%88%B6%E8%AF%AD%E5%8F%A5%E5%92%8C%E6%B5%81%E7%A8%8B%E5%9B%BE" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">7</div>控制语句和流程图</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/08-if%E9%80%89%E6%8B%A9%E7%BB%93%E6%9E%84" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">8</div>if选择结构</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/09-switch%E9%80%89%E6%8B%A9%E7%BB%93%E6%9E%84" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">9</div>switch选择结构</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/10-%E5%BE%AA%E7%8E%AF%E7%BB%93%E6%9E%84" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">10</div>循环结构</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/11-%E5%A4%9A%E9%87%8D%E5%BE%AA%E7%8E%AF" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">11</div>多重循环</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/12-%E7%A8%8B%E5%BA%8F%E8%B0%83%E8%AF%95%E5%85%A5%E9%97%A8" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">12</div>程序调试入门</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/13-%E4%B8%80%E7%BB%B4%E6%95%B0%E7%BB%84" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">13</div>一维数组</p><!--]--></a><!----></div><!----></div><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/14-%E5%A4%9A%E7%BB%B4%E6%95%B0%E7%BB%84" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">14</div>多维数组</p><!--]--></a><!----></div><!----></div><!--]--></div></section></div><div class="group" data-v-802ad7d8><section class="VPSidebarItem level-0 collapsible collapsed" data-v-802ad7d8 data-v-95d837d1><div class="item" role="button" tabindex="0" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><h2 class="text" data-v-95d837d1>Java面向对象 (1篇)</h2><div class="caret" role="button" aria-label="toggle section" tabindex="0" data-v-95d837d1><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="caret-icon" data-v-95d837d1><path d="M9,19c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l5.3-5.3L8.3,6.7c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l6,6c0.4,0.4,0.4,1,0,1.4l-6,6C9.5,18.9,9.3,19,9,19z"></path></svg></div></div><div class="items" data-v-95d837d1><!--[--><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/02-Java%E9%9D%A2%E5%90%91%E5%AF%B9%E8%B1%A1/01-%E7%B1%BB%E5%92%8C%E5%AF%B9%E8%B1%A1" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-red mr-[6px]" style="font-weight: 550; display: inline-block;">1</div>类和对象</p><!--]--></a><!----></div><!----></div><!--]--></div></section></div><div class="group" data-v-802ad7d8><section class="VPSidebarItem level-0 collapsible collapsed" data-v-802ad7d8 data-v-95d837d1><div class="item" role="button" tabindex="0" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><h2 class="text" data-v-95d837d1>Java高级特性 (1篇)</h2><div class="caret" role="button" aria-label="toggle section" tabindex="0" data-v-95d837d1><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="caret-icon" data-v-95d837d1><path d="M9,19c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l5.3-5.3L8.3,6.7c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l6,6c0.4,0.4,0.4,1,0,1.4l-6,6C9.5,18.9,9.3,19,9,19z"></path></svg></div></div><div class="items" data-v-95d837d1><!--[--><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/03-Java%E9%AB%98%E7%BA%A7%E7%89%B9%E6%80%A7/01-%E9%9B%86%E5%90%88%E4%B8%8E%E6%B3%9B%E5%9E%8B-1" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-red mr-[6px]" style="font-weight: 550; display: inline-block;">1</div>集合与泛型-1</p><!--]--></a><!----></div><!----></div><!--]--></div></section></div><div class="group" data-v-802ad7d8><section class="VPSidebarItem level-0 collapsible collapsed" data-v-802ad7d8 data-v-95d837d1><div class="item" role="button" tabindex="0" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><h2 class="text" data-v-95d837d1>附录 (1篇)</h2><div class="caret" role="button" aria-label="toggle section" tabindex="0" data-v-95d837d1><svg xmlns="http://www.w3.org/2000/svg" aria-hidden="true" focusable="false" viewbox="0 0 24 24" class="caret-icon" data-v-95d837d1><path d="M9,19c-0.3,0-0.5-0.1-0.7-0.3c-0.4-0.4-0.4-1,0-1.4l5.3-5.3L8.3,6.7c-0.4-0.4-0.4-1,0-1.4s1-0.4,1.4,0l6,6c0.4,0.4,0.4,1,0,1.4l-6,6C9.5,18.9,9.3,19,9,19z"></path></svg></div></div><div class="items" data-v-95d837d1><!--[--><div class="VPSidebarItem level-1 is-link" data-v-95d837d1 data-v-95d837d1><div class="item" data-v-95d837d1><div class="indicator" data-v-95d837d1></div><a class="VPLink link link" href="/courses/java/04-%E9%99%84%E5%BD%95/01-CentOS%E5%AE%89%E8%A3%85JDK" data-v-95d837d1><!--[--><p class="text" data-v-95d837d1><div class="text-color-red mr-[6px]" style="font-weight: 550; display: inline-block;">1</div>CentOS 8.2 安装 JDK 1.8.0_202</p><!--]--></a><!----></div><!----></div><!--]--></div></section></div><!--]--><!--[--><!--]--></nav></aside><div class="VPContent has-sidebar" id="VPContent" data-v-03322d68 data-v-2c336b25><div class="VPDoc has-sidebar has-aside" data-v-2c336b25 data-v-53ed897c><!--[--><!--]--><div class="container" data-v-53ed897c><div class="aside" data-v-53ed897c><div class="aside-curtain" data-v-53ed897c></div><div class="aside-container" data-v-53ed897c><div class="aside-content" data-v-53ed897c><div class="VPDocAside" data-v-53ed897c data-v-3d450548><!--[--><!--]--><!--[--><!--]--><div class="VPDocAsideOutline" role="navigation" data-v-3d450548 data-v-70b38f01><div class="content" data-v-70b38f01><div class="outline-marker" data-v-70b38f01></div><div class="outline-title" role="heading" aria-level="2" data-v-70b38f01>目录</div><nav aria-labelledby="doc-outline-aria-label" data-v-70b38f01><span class="visually-hidden" id="doc-outline-aria-label" data-v-70b38f01> Table of Contents for current page </span><ul class="root" data-v-70b38f01 data-v-e10534d6><!--[--><!--]--></ul></nav></div></div><!--[--><!--]--><div class="spacer" data-v-3d450548></div><!--[--><!--]--><!----><!--[--><!--]--><!--[--><!--]--></div></div></div></div><div class="content" data-v-53ed897c><div class="content-container" data-v-53ed897c><!--[--><!--]--><!----><main class="main" data-v-53ed897c><div style="position:relative;" class="vp-doc _courses_java_01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8_10-%E5%BE%AA%E7%8E%AF%E7%BB%93%E6%9E%84" data-v-53ed897c><div><h1 id="循环结构" tabindex="-1">循环结构 <a class="header-anchor" href="#循环结构" aria-label="Permalink to "循环结构""></a></h1><!----><h2 id="前言" tabindex="-1">前言 <a class="header-anchor" href="#前言" aria-label="Permalink to "前言""></a></h2><p><strong>C：</strong> 在 <a href="./07-控制语句和流程图">《控制语句和流程图》</a>篇中，笔者介绍了三种控制语句，每种控制语句都有它能解决的问题范围。例如：顺序控制语句可以解决“流水‘步骤，选择控制语句可以解决条件判断问题。</p><p>本篇我们要学习最后一种控制语句：循环控制语句。它可以用来解决业务中的重复、有规律性的问题。</p><p><img src="/assets/202010080736666.i8mh7Wg0.gif" alt="202010080736666"></p><h2 id="什么是循环" tabindex="-1">什么是循环 <a class="header-anchor" href="#什么是循环" aria-label="Permalink to "什么是循环""></a></h2><h3 id="生活" tabindex="-1">生活 <a class="header-anchor" href="#生活" aria-label="Permalink to "生活""></a></h3><div class="tip custom-block"><p class="custom-block-title">循环 [circulate;circle]</p><ul><li>以环形、回路或轨道运行;</li><li>沿曲折的路线运行;</li><li>特指运行一周而回到原处,再转。</li><li>或说反复地连续做某事。</li></ul></div><p>计算机程序是来源于生活程序的。生活中，我们上班、上学、坚持某个习惯等都算是一个循环过程。</p><p><img src="/assets/202010080737123.42C-UlHe.png" alt="202010080737123"></p><p>甚至，在近两年的日常发言方面还有一个梗：“人类的本质是复读机”。</p><p><img src="/assets/202010080737815.6uaAokny.jpeg" alt="202010080737815"></p><h3 id="计算机" tabindex="-1">计算机 <a class="header-anchor" href="#计算机" aria-label="Permalink to "计算机""></a></h3><p>生活中有循环需求，在计算机程序中，类似的需求也是数不胜数的。</p><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>在不少实际问题中有许多具有规律性的重复操作，因此在程序中就需要重复执行某些语句。循环结构是在一定条件下反复执行某段程序的流程结构，被反复执行的程序被称为循环体（循环操作）。[1]</p></div><p><strong>案例需求：熊大 Java 考试成绩未达到自己的目标。为了表明自己勤奋学习的决心，他决定写一百遍“好好学习，天天向上！”</strong></p><p>这么有上进心的学生，真是令老师喜欢！那如何用 Java 代码来实现输出100遍 ”好好学习，天天向上” 呢？</p><p><img src="/assets/202010080737888.Ze6rFEsm.png" alt="202010080737888"></p><p>好像没什么毛病，如果掌握了 Ctrl+C 和 Ctrl+V，就变得更加简单了。但是如果现在这位有上进心的学生，决定写10000遍呢？哪怕是用CV大法，这代码工作量也是吓坏个人 ！</p><p>好在，Java 语言为我们准备了三种循环结构语法，它们都可以轻松解决此需求，接下来一起去看看吧。</p><h2 id="while循环" tabindex="-1">while循环 <a class="header-anchor" href="#while循环" aria-label="Permalink to "while循环""></a></h2><p>while 循环是一种经典的循环结构语法，不仅仅是在 Java 语言中，其他的编程语言中也有类似的概念和语法。</p><p><img src="/assets/202010080738759.fZj09zr1.png" alt="202010080738759"></p><h3 id="语法" tabindex="-1">语法 <a class="header-anchor" href="#语法" aria-label="Permalink to "语法""></a></h3><p>它的语法，宽松来讲包含两个组成，和 if 选择结构非常相似。</p><ul><li>循环条件</li><li>循环体</li></ul><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (循环条件) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> 循环体</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">/</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><p>从流程图中，我们可以看出它和选择结构的主要区别在于： <strong>当条件成立且执行完操作后，它不会直接结束，而是会再次进入条件判断，直到条件不成立为止。</strong></p><!----><h3 id="使用" tabindex="-1">使用 <a class="header-anchor" href="#使用" aria-label="Permalink to "使用""></a></h3><p>接下来我们通过案例来掌握一下使用步骤。</p><details class="details custom-block"><summary>案例需求1：解决上方熊大的问题。</summary><p><strong>思路分析：</strong></p><ol><li><p>此案例为重复性步骤需求，采用循环控制语句解决</p></li><li><p>要应用 while 循环，需要先确定此案例中，循环的两个固定组成部分</p><ul><li><p>循环条件：<code><= 100</code></p></li><li><p>循环操作：输出 "好好学习，天天向上"</p></li></ul></li><li><p>套用 while 循环的语法来编写代码</p><p>宽松的语法只考虑循环条件和循环操作即可。但为了让各位同学编写代码时可以形成一个完整步骤思路，笔者对语法步骤做了扩展，扩展为了4部分，这样你在用循环解决问题时，就直接可以去思考4部分的组成。</p><ul><li><p>初始化 循环变量：为循环条件表达式，准备一个起始变量</p></li><li><p>循环条件</p></li><li><p>循环操作</p></li><li><p>循环出口：对循环条件表达式中的变量进行变化，让循环可以在指定时机结束</p></li></ul></li><li><p>检查是否正常在业务完成后退出循环</p></li></ol><p>(上方这多出来的两个组成，其实是为了补齐循环条件的使用。)</p></details><p><strong>代码实现：</strong></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 1.初始化 循环变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 2.循环条件</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 100</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 3.循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "遍：好好学习，天天向上！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 4.循环出口</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 借助变量 i 来作循环条件，如果 i 的值不变动，会出现死循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>你看应用循环结构语法之后，简单的几行代码就搞定了原来的问题。而且如果要更改输出的次数，只需要改一下循环条件部分即可。</p></div><details class="details custom-block"><summary>案例需求2：实现打印50份试卷。</summary><p><strong>思路分析：</strong></p><ol><li>此案例为重复性步骤需求，采用循环控制语句解决</li><li>要应用 while 循环，需要先确定此案例中，循环的两个固定组成部分 <ul><li><p>循环条件：<code><= 50</code></p></li><li><p>循环操作：打印试卷</p></li></ul></li><li>套用 while 循环的语法来编写代码</li><li>检查是否正常在业务完成后退出循环</li></ol></details><p><strong>代码实现：</strong></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 1.初始化 循环变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 2.循环条件</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 50</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 3.循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"正在打印第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "份试卷"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 4.循环出口</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><h2 id="do-while循环" tabindex="-1">do-while循环 <a class="header-anchor" href="#do-while循环" aria-label="Permalink to "do-while循环""></a></h2><p><strong>案例需求：老师每天检查张浩的学习任务是否合格，如果不合格，则继续进行。老师给熊二安排的每天的学习任务为：上午阅读教材，学习理论部分，下午上机编程，掌握代码部分。</strong></p><p>这个需求，大致一看可确定也是采用循环来解决，其中循环的两个要素：</p><ul><li><p>循环条件：检查不合格继续进行</p></li><li><p>循环操作：学习任务（上午阅读教材，学习理论部分，下午上机编程，掌握代码部分）</p></li></ul><p>但是我们发现，该案例与刚才的两个案例，有显著不同的地方：</p><ul><li>逻辑顺序：它的逻辑是先进行学习任务（循环操作），然后再由老师检查（循环条件）。</li><li>条件复杂：它的条件也不再是普通次数递增，而是判断是否合格。</li></ul><p>面对此需求，条件复杂倒是可以更改相应变量即可，但逻辑顺序方面却无法与 while 循环的流程相符（ <strong>while 循环是先执行判断，再进行循环操作</strong> ）。因此，Java 语言提供的第二种循环结构语法可以派上用场了： <code>do-while</code> 循环。</p><h3 id="语法-1" tabindex="-1">语法 <a class="header-anchor" href="#语法-1" aria-label="Permalink to "语法""></a></h3><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">do</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> 循环体</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">/</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">} </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (循环条件);</span></span></code></pre></div><p>从流程图中，我们可以看出：<code>do-while</code> 循环的执行讲究一个先 do（循环操作），然后再执行循环条件。而且 <strong>无论条件是否能成立，它至少会执行一次循环操作</strong> 。</p><!----><h3 id="使用-1" tabindex="-1">使用 <a class="header-anchor" href="#使用-1" aria-label="Permalink to "使用""></a></h3><p>我们来使用 <code>do-while</code> 解决下熊二的问题。</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 1.初始化循环变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> result;</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 套用do-while语句</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">do</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 2.循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"熊二上午阅读教材，学习理论部分。"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"熊二下午上机编程，掌握代码部分。"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 3.循环出口</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"老师检查是否合格(y/n)："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> result </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">} </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"n"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">equals</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(result)); </span><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 4.循环条件</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"今日学习圆满！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span></code></pre></div><h2 id="for循环" tabindex="-1">for循环 <a class="header-anchor" href="#for循环" aria-label="Permalink to "for循环""></a></h2><p>学完了 while 系列的循环语法，接下来笔者再带你认识最后一种循环语法：for循环。</p><h3 id="why" tabindex="-1">Why？ <a class="header-anchor" href="#why" aria-label="Permalink to "Why？""></a></h3><p><strong>for循环是我们后期高频次使用的一种循环语法！</strong> 为什么高频使用，一定有缘由，看看下方 “输出100遍，好好学习” 实现对比！</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// =============while循环=============</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 1.初始化 循环变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 2.循环条件</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 100</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 3.循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "遍：好好学习，天天向上！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 4.循环出口</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 借助变量 i 来作循环条件，如果 i 的值不变动，会出现死循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// =============for循环=============</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 100</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "遍：好好学习，天天向上！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><p>显而易见，<strong>在循环次数固定的情况下，for 循环比while 循环更简洁</strong> 。</p><h3 id="语法-2" tabindex="-1">语法 <a class="header-anchor" href="#语法-2" aria-label="Permalink to "语法""></a></h3><p>for 循环的语法要更加简洁，更加灵活，但是上方总结的循环四要素是没有变化的。只不过它要求我们将循环中经常忘却的几个组成要素，先指定好，这样就可以更专注于循环操作了。所以你可以将 for 循环理解为是 while 循环的延伸。（就像多重 if 延伸为 switch 选择结构一样）</p><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>对于笔者个人来讲，如果 for 和 while 都能解决的问题，我更偏向于 for 的使用。因为在使用 while 循环时，自上而下的编写代码，经常忘却的就是循环出口。</p></div><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (初始化 循环变量; 循环条件; 循环出口) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> 循环体</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">/</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">循环操作</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><h3 id="使用-2" tabindex="-1">使用 <a class="header-anchor" href="#使用-2" aria-label="Permalink to "使用""></a></h3><details class="details custom-block"><summary>案例需求1：循环输入某同学期末考试的5门课成绩，并计算平均分。</summary><p><strong>思路分析：</strong>（平均分：总成绩 / 数量）</p><ol><li><p>此案例为重复性步骤需求，采用循环控制语句解决</p></li><li><p>确定此案例中，循环的两个固定组成部分</p><ul><li>循环条件：<code><= 5</code></li><li>循环操作：输入每门课成绩，并累加求和（+=）</li></ul></li><li><p>由于是固定次数循环，套用 for 循环的语法来编写代码</p><ul><li><p>初始化 循环变量：为循环条件表达式，准备一个起始变量</p></li><li><p>循环条件</p></li><li><p>循环操作</p></li><li><p>循环出口：对循环条件表达式中的变量进行变化，让循环可以在指定时机结束</p></li></ul></li><li><p>检查是否正常在业务完成后退出循环</p></li></ol></details><p><img src="/assets/202010080739719.cn9q4sHI.png" alt="202010080739719"></p><p><strong>代码实现：</strong></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入学生姓名："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> name</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 定义变量存储成绩和</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 输入每门课成绩</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "门课的成绩："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> score</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextDouble</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 累加成绩和</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> score;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 计算平均分，平均分 = 成绩和 / 课数量</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> avg</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">/</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(name </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "的平均分为："</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> avg);</span></span></code></pre></div><details class="details custom-block"><summary>案例需求2：输出如图所示加法表。</summary><p><strong>思路分析：</strong></p><ol><li><p>此案例为重复性步骤需求，采用循环控制语句解决</p></li><li><p>确定此案例中，循环的两个固定组成部分</p><ul><li>循环条件：<code><= 输入的值</code></li><li>循环操作：要输出加法运算 加法运算的两个操作数 <ul><li>第一个操作数：从0递增到你输入的值</li><li>第二个操作数：从你输入的值递减到0</li></ul></li></ul></li><li><p>由于是固定次数循环，套用 for 循环的语法来编写代码</p><ul><li>初始化 循环变量：为循环条件表达式，准备一个起始变量</li><li>循环条件</li><li>循环操作</li><li>循环出口：对循环条件表达式中的变量进行变化，让循环可以在指定时机结束</li></ul></li><li><p>检查是否正常在业务完成后退出循环</p></li></ol></details><p><img src="/assets/202010080739888.XIbLhiPc.png" alt="202010080739888"></p><p><strong>代码实现：</strong></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入一个值："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextInt</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"根据这个值可以输出以下加法表："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 套用 for 语法</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 注意：int i = 0, j = num; 这也是变量定义的方式，但不常用</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">, j </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num; i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">, j</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">--</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> " + "</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> " = "</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j));</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><p>或者是：</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入一个值："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextInt</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"根据这个值可以输出以下加法表："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 套用 for 语法</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 定义两个计算变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num;</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num;) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> " + "</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> " = "</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j));</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 循环出口</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> j</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">--</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><h3 id="注意事项" tabindex="-1">注意事项 <a class="header-anchor" href="#注意事项" aria-label="Permalink to "注意事项""></a></h3><ul><li>for 循环的三大项都可以省略，但是两个 <code>;</code> 号不能省！省略了三大项之后，就成了死循环。</li><li>for 循环中的初始化变量和循环出口可以单独拿出来，比如为了提升变量作用域的情况。</li><li>for 循环只能用于循环次数固定的场景。</li></ul><h2 id="三种循环的区别" tabindex="-1">三种循环的区别 <a class="header-anchor" href="#三种循环的区别" aria-label="Permalink to "三种循环的区别""></a></h2><p>执行顺序区别：</p><ul><li>while 循环：先判断再执行</li><li>do-while 循环：先执行再判断。初始情况不满足循环条件时，do-while 至少也会执行一次。</li><li>for 循环：先判断再执行</li></ul><p>适用情况区别：</p><ul><li>循环次数固定的情况，通常选用 for 循环</li><li>循环次数不确定的情况，通常选用 while 或 do-while 循环</li></ul><h2 id="死循环" tabindex="-1">死循环 <a class="header-anchor" href="#死循环" aria-label="Permalink to "死循环""></a></h2><p>上方介绍循环时，笔者大量提到了一个概念：死循环。死循环，就是当你循环没有出口，导致循环无法结束的一种现象。</p><p>下方是最简单的三种死循环代码，但只要循环条件或循环出口的错误或缺失，其实都会导致死循环出现。</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;">true</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> </span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">do</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> {</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">} </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;">true</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span></code></pre></div><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (;;) {</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><p>按理说死循环是不好的情况，但正如：“功法没有正邪之分，主要看使用者。“ 合理使用死循环会让你的程序编写更加便捷。</p><p>例如：当你 <strong>不知道一个循环什么时候结束的时候</strong>，使用死循环会更加合适。但一般它要配合跳转语句来使用。</p><h3 id="跳转语句" tabindex="-1">跳转语句 <a class="header-anchor" href="#跳转语句" aria-label="Permalink to "跳转语句""></a></h3><h4 id="break" tabindex="-1">break <a class="header-anchor" href="#break" aria-label="Permalink to "break""></a></h4><p>生活中参加长跑比赛，如果在比赛过程中身体不支/不适，是可以退出比赛的。</p><p>而程序中，也有需要在指定的情况下就不要再执行循环的需求，这时候跳转语句们就可以灵活的调度这个循环流程。</p><p><code>break</code> 关键字，在 switch 语句中我们就见过，表示中断的意思。它还可以使用在三大循环结构中，此时它表示 <strong>结束当前所在的循环流程，跳转到循环块外的下一条语句</strong> 。</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 伪代码：4000米长跑</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 10</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (体力不支) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 退出比赛</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> break</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> }</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><p><strong>案例需求：循环录入某学生5门课的成绩并计算平均分，如果某分数录入为负，停止录入并提示录入错误。</strong></p><p><img src="/assets/202010080739999.05_bJQmM.png" alt="202010080739999"></p><p>该需求，就是刚才 for 循环中实现过的案例，只不过是增加了些许要求。</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入学生姓名："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> name</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 提升作用域</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 如果 i 定义在for循环块中，那它就只能在for循环块中使用。</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "门课的成绩："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> score</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextDouble</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 如果输入了负数，提示错误并结束循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (score </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"分数录入错误！请重新开始录入！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> break</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> }</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> score;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 提前结束循环则不需要进行平均分计算</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">></span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> avg</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> sum </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">/</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 5</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(name </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "的平均分为："</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> avg);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div><h4 id="continue" tabindex="-1">continue <a class="header-anchor" href="#continue" aria-label="Permalink to "continue""></a></h4><p>除了 <code>break</code> 之外，还有一个跳转语句：<code>continue</code>。顾名思义，它的作用是 <strong>跳过本次循环体中余下尚未执行的语句，立即进行下一次的循环条件判定，可以理解为仅结束本次循环</strong> 。</p><p><strong>案例需求：使用循环 + continue实现，循环录入 Java 课的学生成绩，统计分数大于等于80分的学生比例。</strong></p><p><img src="/assets/202010080740608.FGnON5xu.png" alt="202010080740608"></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入班级总人数："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextInt</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 设 >= 80分的学生人数</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> count</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 0</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">for</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">int</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><=</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num; i</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入第"</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> i </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "位学生的成绩："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> score</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">nextDouble</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 统计成绩 >= 80分以上的学生人数</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (score </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"><</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 80</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 结束本次循环，进入下一次循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> continue</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> }</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 累加人数</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> count </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;">// 计算</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">double</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> percent</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> count </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">*</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 1.0</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> /</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> num </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">*</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 100</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">; </span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"80分以上的学生人数为："</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> count);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"80分以上的学生所占的比例为："</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> +</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> percent </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">+</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "%"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span></code></pre></div><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>这个案例，continue不是必须的，我们也可以把统计人数部分代码更换为：</p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (score </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">></span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> 80</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> count </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">++</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span></code></pre></div></div><h3 id="死循环-跳转语句" tabindex="-1">死循环 + 跳转语句 <a class="header-anchor" href="#死循环-跳转语句" aria-label="Permalink to "死循环 + 跳转语句""></a></h3><p>好了，再介绍完跳转语句，笔者给大家介绍一种死循环结合跳转语句，实现重复输入的应用。</p><ul><li>死循环的使用，可以令程序不结束永远执行下去</li><li>break的使用，可以结束该循环</li><li>continue的使用，可以结束本次循环，进入下次循环</li></ul><p><img src="/assets/202010080741306.EaDWboIl.png" alt="202010080741306"></p><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;">true</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入用户名："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> username</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入用户密码："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> password</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 失败重输</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">!</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"admin"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">equals</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(username) </span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> &&</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "abcd123"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">equals</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(password))) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"登录失败！请重新输入!"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 结束本次循环，进入下次循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> continue</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> }</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 结束死循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> break</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">}</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"登录成功！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span></code></pre></div><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>是不是感觉稍微有些烧脑了？多写几次就好了！它还可以写成下方这种。</p><p>但笔者 <strong>个人</strong> 还是比较喜欢死循环的写法，只要"时机"到了，随时结束或进入下一次，很直接，很纯粹，很果断。</p></div><div class="language-java vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">java</span><pre class="shiki shiki-themes github-light github-dark-dimmed vp-code"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> new</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;"> Scanner</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(System.in);</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">boolean</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> flag;</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">do</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> {</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 初始化 循环变量</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 初始为true，只有当登录成功才将flag状态改为false以结束循环</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> flag </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> true</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入用户名："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> username</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">print</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"请输入用户密码："</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> String</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> password</span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> input.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">next</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">();</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 失败重输</span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"admin"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">equals</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(username) </span></span>
|
||
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;"> &&</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;"> "abcd123"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">equals</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(password)) {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"登录成功！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#768390;"> // 更改循环状态</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> flag </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">=</span><span style="--shiki-light:#005CC5;--shiki-dark:#6CB6FF;"> false</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">;</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">else</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> {</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> System.out.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#DCBDFB;">println</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#96D0FF;">"登录失败！请重新输入！"</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">);</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> }</span></span>
|
||
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;">} </span><span style="--shiki-light:#D73A49;--shiki-dark:#F47067;">while</span><span style="--shiki-light:#24292E;--shiki-dark:#ADBAC7;"> (flag);</span></span></code></pre></div><h2 id="答题环节" tabindex="-1">答题环节 <a class="header-anchor" href="#答题环节" aria-label="Permalink to "答题环节""></a></h2><h3 id="计算和" tabindex="-1">计算和 <a class="header-anchor" href="#计算和" aria-label="Permalink to "计算和""></a></h3><details class="details custom-block"><summary>需求：使用 while、do-while 以及 for 循环三种编程方式分别实现：计算100以内（包括100）的偶数之和。</summary><p>提示：偶数，能够被 2 整除的数字被称为偶数。例如：4 % 2 == 0，4为偶数。</p></details><h3 id="打印数列" tabindex="-1">打印数列 <a class="header-anchor" href="#打印数列" aria-label="Permalink to "打印数列""></a></h3><p><strong>需求：</strong> 使用循环输出 100、95、90、85、.......5。</p><h3 id="输出所有的水仙花数" tabindex="-1">输出所有的水仙花数 <a class="header-anchor" href="#输出所有的水仙花数" aria-label="Permalink to "输出所有的水仙花数""></a></h3><details class="details custom-block"><summary>需求：使用单层循环实现所有水仙花数的输出。</summary><p><strong>提示：什么是水仙花数？</strong></p><ol><li><p>水仙花数都是三位数</p></li><li><p>水仙花数的个位的立方 + 十位立方 + 百位立方 = 水仙花数字本身</p></li></ol></details><h3 id="输出星期数" tabindex="-1">输出星期数 <a class="header-anchor" href="#输出星期数" aria-label="Permalink to "输出星期数""></a></h3><p><strong>需求：</strong> 从键盘输入一位整数，当输入1 ~ 7 时，输出"星期一" ~ "星期日"。</p><ul><li>输入其他数字时，提示用户重新输入。</li><li>输入数字0，程序结束</li></ul><p><img src="/assets/202010080741825.EtL9Slco.png" alt="202010080741825"></p><h2 id="参考文献" tabindex="-1">参考文献 <a class="header-anchor" href="#参考文献" aria-label="Permalink to "参考文献""></a></h2><p>[1]张桂珠、张平、陈爱国．Java面向对象程序设计（jdk1.6）第三版：北京邮电大学出版社，2005</p><h2 id="后记" tabindex="-1">后记 <a class="header-anchor" href="#后记" aria-label="Permalink to "后记""></a></h2><p>我想，学完这一篇的同学们一定会开始有些许头疼。因为循环它开始变得有所抽象，简单的几行代码却要表述出成百上千次操作，循环操作越是复杂，那需要的空间思维越是庞大，不过别担心，下一篇，笔者解救你。</p><p>另外，笔者在本篇给相同的需求，反复给出不同的解决方法，这对于初次学习，以及"刻板化"学习的同学会有些难受，因为不知道选择哪个了。</p><div class="tip custom-block"><p class="custom-block-title">笔者说</p><p>实际上，生活从来不是一个"刻板化"的步骤，生活中遇到的问题也不总是“刻板化”的来解决，程序亦是如此，千人千面，千题千解。</p><p>笔者给你一个个人建议，根据自身情况，先选择一种最喜欢的解决方法，然后当这种解决方法怎么都无法解决问题的时候，考虑下另一种或更多种。</p></div><div class="info custom-block"><p class="custom-block-title">笔者说</p><p>对于技术的学习，笔者一贯遵循的步骤是：先用最最简单的 demo 让它跑起来，然后学学它的最最常用 API 和 配置让自己能用起来，最后熟练使用的基础上，在空闲时尝试阅读它的源码让自己能够洞彻它的运行机制，部分问题出现的原因，同时借鉴这些技术实现来提升自己的代码高度。</p><p>所以在笔者的文章中，前期基本都是小白文，仅仅穿插很少量的源码研究。当然等小白文更新多了，你们还依然喜欢，后期会不定时专门对部分技术的源码进行解析。</p></div></div></div></main><footer class="VPDocFooter" data-v-53ed897c data-v-f3af8004><!--[--><!--[--><!--[--><!--[--><!----><!--]--><!--]--><!--]--><!--]--><div class="edit-info" data-v-f3af8004><div class="edit-link" data-v-f3af8004><a class="VPLink link vp-external-link-icon no-icon edit-link-button" href="https://github.com/Charles7c/charles7c.github.io/edit/main/docs/courses/java/01-Java语法入门/10-循环结构.md" target="_blank" rel="noreferrer" data-v-f3af8004><!--[--><svg xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24" class="edit-link-icon" aria-label="edit icon" data-v-f3af8004><path d="M18,23H4c-1.7,0-3-1.3-3-3V6c0-1.7,1.3-3,3-3h7c0.6,0,1,0.4,1,1s-0.4,1-1,1H4C3.4,5,3,5.4,3,6v14c0,0.6,0.4,1,1,1h14c0.6,0,1-0.4,1-1v-7c0-0.6,0.4-1,1-1s1,0.4,1,1v7C21,21.7,19.7,23,18,23z"></path><path d="M8,17c-0.3,0-0.5-0.1-0.7-0.3C7,16.5,6.9,16.1,7,15.8l1-4c0-0.2,0.1-0.3,0.3-0.5l9.5-9.5c1.2-1.2,3.2-1.2,4.4,0c1.2,1.2,1.2,3.2,0,4.4l-9.5,9.5c-0.1,0.1-0.3,0.2-0.5,0.3l-4,1C8.2,17,8.1,17,8,17zM9.9,12.5l-0.5,2.1l2.1-0.5l9.3-9.3c0.4-0.4,0.4-1.1,0-1.6c-0.4-0.4-1.2-0.4-1.6,0l0,0L9.9,12.5z M18.5,2.5L18.5,2.5L18.5,2.5z"></path></svg> 不妥之处，敬请雅正<!--]--></a></div><div class="last-updated" data-v-f3af8004><p class="VPLastUpdated" data-v-f3af8004 data-v-a25eb6f3>最后更新: <time datetime="2022-09-24T06:08:24.000Z" data-v-a25eb6f3></time></p></div></div><nav class="prev-next" data-v-f3af8004><div class="pager" data-v-f3af8004><a class="VPLink link pager-link prev" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/09-switch%E9%80%89%E6%8B%A9%E7%BB%93%E6%9E%84" data-v-f3af8004><!--[--><span class="desc" data-v-f3af8004>上一篇</span><span class="title" data-v-f3af8004><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">9</div>switch选择结构</span><!--]--></a></div><div class="pager" data-v-f3af8004><a class="VPLink link pager-link next" href="/courses/java/01-Java%E8%AF%AD%E6%B3%95%E5%85%A5%E9%97%A8/11-%E5%A4%9A%E9%87%8D%E5%BE%AA%E7%8E%AF" data-v-f3af8004><!--[--><span class="desc" data-v-f3af8004>下一篇</span><span class="title" data-v-f3af8004><div class="text-color-gray mr-[6px]" style="font-weight: 550; display: inline-block;">11</div>多重循环</span><!--]--></a></div></nav></footer><!--[--><!--[--><!--[--><div id="comment-container"></div><!--]--><!--]--><!--]--></div></div></div><!--[--><!--]--></div></div><!----><!--[--><!--]--></div></div>
|
||
<script>window.__VP_HASH_MAP__=JSON.parse("{\"about_me.md\":\"yl4MsNR1\",\"categories_solutions_index.md\":\"JPFJaff4\",\"categories_fragments_index.md\":\"lRTNURvo\",\"categories_issues_2021_12_01_f盘上的回收站已损坏。是否清空该驱动器上的回收站.md\":\"dANDLbnx\",\"categories_issues_2021_12_10_command line is too long. shorten command line for xxx or also for spring boot default configuration.md\":\"PXnmw2TY\",\"categories_issues_2021_12_13_无法访问f盘。文件或目录损坏且无法读取.md\":\"ly-jJhLg\",\"categories_issues_2022_08_31_springboot项目引入openfeign后无法启动.md\":\"ChRCkQV5\",\"categories_issues_2022_08_11_执行shell脚本，报java command not found.md\":\"M4ZLKe1m\",\"categories_issues_2022_10_15_解决windows桌面部分快捷方式图标变为空白的问题.md\":\"Zuxd2KdY\",\"categories_issues_2022_10_25_解决centos8执行yum安装报错.md\":\"vWOngd9g\",\"categories_fragments_2022_03_27_修改git所有提交记录中的作者和邮箱.md\":\"OvDDBZd4\",\"courses_java_01-java语法入门_12-程序调试入门.md\":\"1LT3Uu5K\",\"about_index.md\":\"aZfz3sjq\",\"courses_java_01-java语法入门_03-初识eclipse.md\":\"VIICcUYm\",\"courses_java_01-java语法入门_05-变量和常量.md\":\"wVbb047E\",\"courses_java_01-java语法入门_07-控制语句和流程图.md\":\"t61wREmj\",\"courses_java_01-java语法入门_14-多维数组.md\":\"C3Jtu4yX\",\"courses_java_02-java面向对象_01-类和对象.md\":\"A4c0BkF0\",\"courses_java_03-java高级特性_01-集合与泛型-1.md\":\"3f19_0FV\",\"courses_java_04-附录_01-centos安装jdk.md\":\"mrm2xLeJ\",\"courses_java_index.md\":\"Vd-Tt2Gz\",\"courses_java_01-java语法入门_08-if选择结构.md\":\"GylQ89V9\",\"courses_java_01-java语法入门_11-多重循环.md\":\"79go9ddo\",\"categories_solutions_2021_11_18_用java8获取近n天日期.md\":\"r9mp3BOr\",\"categories_fragments_2022_10_26_docker安装openldap.md\":\"mcPLxA8n\",\"index.md\":\"rpby8rrg\",\"courses_mybatis_01-mybatis基础_03-核心配置文件.md\":\"pjBK9LfV\",\"categories_fragments_2019_12_31_个人常用linux命令.md\":\"lx3qwmph\",\"courses_mysql_03-附录_02-docker安装mysql.md\":\"Qay1Rxzf\",\"courses_java_01-java语法入门_02-第一个java程序.md\":\"b9EylDVG\",\"courses_mybatis_index.md\":\"7LMzFTpl\",\"courses_java_01-java语法入门_04-程序和计算机的那点事儿.md\":\"i4Xi0Jl0\",\"courses_java_01-java语法入门_06-常用的运算符.md\":\"ERU0p3Fx\",\"categories_tools_2021_03_06_postman快速入门.md\":\"7P3rh4Zw\",\"courses_java_01-java语法入门_09-switch选择结构.md\":\"p1ZypRLa\",\"courses_mysql_03-附录_01-centos安装mysql.md\":\"ZEGR5OmN\",\"categories_fragments_2022_12_07_网站开启灰色显示.md\":\"ALiJge8d\",\"categories_fragments_2022_03_28_为指定git仓库单独配置用户名和邮箱.md\":\"qMYHQNJe\",\"courses_mybatis_02-mybatis-plus基础_05-代码生成器.md\":\"hjpH5d8x\",\"courses_java_01-java语法入门_01-开发环境搭建.md\":\"JchJHevH\",\"categories_issues_2022_11_04_解决docker安装prometheus启动报错的问题.md\":\"wlwkdFKi\",\"categories_tools_index.md\":\"qDqYFV-P\",\"categories_issues_2022_09_23_解决无法重复读取请求体和响应体的问题.md\":\"QBFvmfGv\",\"categories_fragments_2022_10_01_个人常用docker命令.md\":\"tQHhdswU\",\"categories_fragments_2022_10_06_个人常用快捷键.md\":\"7DmE2Sdn\",\"courses_mysql_index.md\":\"6rziEA5O\",\"categories_issues_2021_12_11_sql 注入攻击风险.md\":\"rljfD_Fi\",\"categories_issues_2022_10_29_docker设置网络代理.md\":\"5gbvC2uf\",\"courses_mybatis_01-mybatis基础_08-动态sql.md\":\"EiHlJ807\",\"courses_mybatis_01-mybatis基础_07-sql映射文件之缓存元素.md\":\"9orUXUze\",\"categories_fragments_2022_08_29_内网centos服务器设置网络代理.md\":\"Wz9Gyo3N\",\"categories_fragments_2022_10_05_个人常用git命令.md\":\"H2ehuVi6\",\"archives.md\":\"hEvO1jAg\",\"categories_solutions_2021_11_22_一条sql查询今年每月统计信息.md\":\"2pLzv9Tp\",\"courses_mybatis_01-mybatis基础_02-核心对象.md\":\"J2u3OyyP\",\"categories_fragments_2023_12_21_一文详解限流接口实现.md\":\"HHXYHaRJ\",\"categories_issues_2021_12_08_for循环中删除集合元素隐藏的陷阱.md\":\"HaXmdlA5\",\"courses_mybatis_02-mybatis-plus基础_04-条件构造器.md\":\"v-MWEs-l\",\"categories_fragments_2022_03_25_合并两个git仓库的历史提交记录.md\":\"e24riSJ9\",\"categories_fragments_2019_12_28_个人sql优化技巧.md\":\"YWYf6RFb\",\"courses_java_01-java语法入门_10-循环结构.md\":\"z73Bcwe8\",\"courses_mybatis_01-mybatis基础_01-快速入门.md\":\"KXcjGx0w\",\"categories_fragments_2019_12_29_个人常用stream使用技巧.md\":\"CuDwLpDP\",\"categories_issues_2022_09_05_nginx转发请求，报13：permission denied错误.md\":\"PClZAC2K\",\"courses_mybatis_01-mybatis基础_05-sql映射文件之增删改元素.md\":\"Q1bwfP8k\",\"categories_fragments_2021_05_29_设计模式之单例模式.md\":\"Q_Kk2HQh\",\"categories_issues_2022_11_23_解决maven传递依赖污染的问题.md\":\"GY3psqIs\",\"categories_fragments_2021_03_12_精密计算工具类-bigdecimal.md\":\"zBMJQ_Bo\",\"categories_tools_2021_01_14_初识lombok.md\":\"DDRTdFdf\",\"categories_fragments_2022_02_16_个人常用sql函数.md\":\"3XF3Onqb\",\"courses_mysql_01-mysql基础_01-mysql安装与配置.md\":\"bXq0pYDh\",\"categories_tools_2021_02_22_rdm快速入门.md\":\"-N1bZYLN\",\"categories_tools_2021_03_10_quartz快速入门.md\":\"yXxsG68Z\",\"categories_fragments_2019_12_30_个人常用hutool工具类.md\":\"8YjnAagp\",\"categories_tools_2021_03_04_ardm快速入门.md\":\"zbxPd0TS\",\"courses_mybatis_01-mybatis基础_06-sql映射文件之自定义映射元素.md\":\"yafOyEf1\",\"courses_mybatis_01-mybatis基础_04-sql映射文件之查询元素.md\":\"UYQRCMvg\",\"categories_fragments_2022_10_28_docker安装minio.md\":\"pOrH5sCo\",\"categories_issues_2022_11_06_解决dotnet安装后报错的问题.md\":\"skCbcShV\",\"categories_fragments_2022_10_27_docker安装consul.md\":\"LIu1Q7_o\",\"categories_fragments_2022_10_31_centos安装docker.md\":\"aS1qV9Oq\",\"courses_mybatis_02-mybatis-plus基础_02-增删改操作.md\":\"0wJpZsHd\",\"categories_fragments_2022_03_26_修改git最后一次提交记录的作者和邮箱.md\":\"hSvi24NU\",\"categories_issues_2022_03_24_创建一个自身类的静态对象变量，究竟会如何执行？.md\":\"_sjVm5kR\",\"categories_solutions_2022_09_07_递归查询树型结构数据的性能优化方案.md\":\"zWro2Zfo\",\"courses_mybatis_02-mybatis-plus基础_03-简单查询操作.md\":\"OO_paHtp\",\"categories_fragments_2023_01_06_codereview方法论与实践总结.md\":\"DtmjPS_i\",\"categories_fragments_2022_11_01_使用idea进行远程程序调试.md\":\"0r_fvBId\",\"courses_mybatis_02-mybatis-plus基础_01-快速入门.md\":\"2M92eqRH\",\"categories_issues_2022_01_26_javascript 无法存储 java long 类型数据问题.md\":\"IO54X60W\",\"categories_issues_index.md\":\"Yzlc8cBS\",\"courses_java_01-java语法入门_13-一维数组.md\":\"tyF-2IM9\",\"tags.md\":\"TML_Ecph\"}");window.__VP_SITE_DATA__=JSON.parse("{\"lang\":\"zh-CN\",\"dir\":\"ltr\",\"title\":\"查尔斯的知识库\",\"description\":\"个人技术知识库，记录 & 分享个人碎片化、结构化、体系化的技术知识内容。\",\"base\":\"/\",\"head\":[],\"router\":{\"prefetchLinks\":true},\"appearance\":true,\"themeConfig\":{\"nav\":[{\"text\":\"我的分类\",\"items\":[{\"text\":\"Bug万象集\",\"link\":\"/categories/issues/index\",\"activeMatch\":\"/categories/issues/\"},{\"text\":\"\\\"杂碎\\\"逆袭史\",\"link\":\"/categories/fragments/index\",\"activeMatch\":\"/categories/fragments/\"},{\"text\":\"工具四海谈\",\"link\":\"/categories/tools/index\",\"activeMatch\":\"/categories/tools/\"},{\"text\":\"方案春秋志\",\"link\":\"/categories/solutions/index\",\"activeMatch\":\"/categories/solutions/\"}],\"activeMatch\":\"/categories/\"},{\"text\":\"我的小册\",\"items\":[{\"text\":\"Java基础快速入门\",\"link\":\"/courses/java/index\",\"activeMatch\":\"/courses/java/\"},{\"text\":\"MySQL快速入门\",\"link\":\"/courses/mysql/index\",\"activeMatch\":\"/courses/mysql/\"},{\"text\":\"MyBatis快速入门\",\"link\":\"/courses/mybatis/index\",\"activeMatch\":\"/courses/mybatis/\"}],\"activeMatch\":\"/courses/\"},{\"text\":\"我的标签\",\"link\":\"/tags\",\"activeMatch\":\"/tags\"},{\"text\":\"我的归档\",\"link\":\"/archives\",\"activeMatch\":\"/archives\"},{\"text\":\"关于\",\"items\":[{\"text\":\"关于知识库\",\"link\":\"/about/index\",\"activeMatch\":\"/about/index\"},{\"text\":\"关于我\",\"link\":\"/about/me\",\"activeMatch\":\"/about/me\"}],\"activeMatch\":\"/about/\"}],\"sidebar\":{\"/categories/issues/\":[{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/tiger.svg\\\" title=\\\"虎年\\\" alt=\\\"生肖\\\">\\n 2022年 (12篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>解决 Maven 传递依赖污染的问题\",\"link\":\"/categories/issues/2022/11/23/解决Maven传递依赖污染的问题\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>解决 DotNet 安装完，报错：Couldn't find a valid ICU package installed on the system. Please install libicu using your package manager and try again\",\"link\":\"/categories/issues/2022/11/06/解决DotNET安装后报错的问题\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>解决 Docker 安装 Prometheus 启动报 permission denied 的问题\",\"link\":\"/categories/issues/2022/11/04/解决Docker安装Prometheus启动报错的问题\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>Docker 设置网络代理\",\"link\":\"/categories/issues/2022/10/29/Docker设置网络代理\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>解决 CentOS 8 执行 yum install 报 Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist 的问题\",\"link\":\"/categories/issues/2022/10/25/解决CentOS8执行yum安装报错\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">6</div>解决 Windows 桌面部分快捷方式图标变为空白的问题\",\"link\":\"/categories/issues/2022/10/15/解决Windows桌面部分快捷方式图标变为空白的问题\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">7</div>解决无法重复读取请求体和响应体的问题\",\"link\":\"/categories/issues/2022/09/23/解决无法重复读取请求体和响应体的问题\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">8</div>Nginx转发请求，报13：Permission denied错误\",\"link\":\"/categories/issues/2022/09/05/Nginx转发请求，报13：Permission denied错误\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">9</div>SpringBoot项目引入OpenFeign后无法启动\",\"link\":\"/categories/issues/2022/08/31/SpringBoot项目引入OpenFeign后无法启动\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">10</div>执行Shell脚本，报java: command not found\",\"link\":\"/categories/issues/2022/08/11/执行Shell脚本，报java command not found\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">11</div>创建一个自身类的静态对象变量，究竟会如何执行？\",\"link\":\"/categories/issues/2022/03/24/创建一个自身类的静态对象变量，究竟会如何执行？\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">12</div>JavaScript 无法存储 Java Long 类型数据问题\",\"link\":\"/categories/issues/2022/01/26/JavaScript 无法存储 Java Long 类型数据问题\"}],\"collapsed\":false},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/ox.svg\\\" title=\\\"牛年\\\" alt=\\\"生肖\\\">\\n 2021年 (5篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>无法访问 F:\\\\。文件或目录损坏且无法读取。\",\"link\":\"/categories/issues/2021/12/13/无法访问F盘。文件或目录损坏且无法读取\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>SQL 注入攻击风险\",\"link\":\"/categories/issues/2021/12/11/SQL 注入攻击风险\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>Command line is too long. Shorten command line for XXX or also for Spring Boot default configuration？\",\"link\":\"/categories/issues/2021/12/10/Command line is too long. Shorten command line for XXX or also for Spring Boot default configuration\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>for循环中删除集合元素隐藏的陷阱\",\"link\":\"/categories/issues/2021/12/08/for循环中删除集合元素隐藏的陷阱\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>F:\\\\ 上的回收站已损坏。是否清空该驱动器上的\\\"回收站\\\"?\",\"link\":\"/categories/issues/2021/12/01/F盘上的回收站已损坏。是否清空该驱动器上的回收站\"}],\"collapsed\":true}],\"/categories/fragments/\":[{\"text\":\"<svg style=\\\"display: inline-block; vertical-align: middle; padding-bottom: 3px;\\\" viewBox=\\\"0 0 1920 1024\\\" version=\\\"1.1\\\" xmlns=\\\"http://www.w3.org/2000/svg\\\" width=\\\"30\\\" height=\\\"30\\\"><path d=\\\"M367.488 667.904h423.744v47.232H367.488v-47.232zM320.256 204.352h137.28v68.992h-137.28v-68.992zM367.488 754.112h423.744v48H367.488v-48zM693.76 204.352h137.984v68.992H693.76v-68.992zM507.008 204.352h137.28v68.992h-137.28v-68.992z\\\" p-id=\\\"10749\\\" fill=\\\"#d81e06\\\"></path><path d=\\\"M1792.512 0H127.488C57.472 0 0 57.152 0 127.616v768.768C0 966.72 57.088 1024 127.488 1024h1665.088c69.952 0 127.424-57.152 127.424-127.616V127.616C1920 57.216 1862.912 0 1792.512 0z m-528 175.104h446.976v54.016H1494.72l-24 101.248h206.976V689.6h-57.728V384.32h-289.472v308.224h-57.728v-362.24h140.224l20.992-101.248h-169.472v-53.952z m-996.032-11.2h614.272v167.232h-51.008v-17.28H320.256v17.28H268.48V163.904z m678.784 681.728h-744v-43.52h111.744V454.848h229.504v-48.704H221.248v-42.048h323.264v-39.744h54.016v39.744h331.52v41.984h-331.52v48.768h245.248v347.264h103.488v43.52z m203.264-94.528c0 59.52-30.72 89.28-92.224 89.28-25.472 0-46.016-0.512-61.504-1.472-2.496-22.976-6.528-45.248-12.032-66.752 22.976 5.504 46.72 8.256 71.232 8.256 24 0 35.968-11.52 35.968-34.496V247.872H971.2v-54.72h278.976v54.72H1150.4v503.232z m521.216 121.536c-67.008-55.488-137.28-108.032-210.752-157.504-4.992 9.984-10.496 19.008-16.512 27.008-41.472 57.024-113.28 101.504-215.232 133.504-9.472-16.512-21.504-34.496-35.968-54.016 94.528-27.008 161.28-64.512 200.256-112.512 34.496-44.992 51.776-113.024 51.776-204.032V421.12h57.728v82.496c0 62.528-6.72 115.776-20.224 159.744 84.48 54.016 161.472 107.008 230.976 158.976l-42.048 50.304z\\\" p-id=\\\"10750\\\" fill=\\\"#d81e06\\\"></path><path d=\\\"M367.488 495.36h423.744v47.232H367.488V495.36zM367.488 581.632h423.744v47.232H367.488v-47.232z\\\" p-id=\\\"10751\\\" fill=\\\"#d81e06\\\"></path></svg>\\n 我的置顶 (8篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>个人常用快捷键\",\"link\":\"/categories/fragments/2022/10/06/个人常用快捷键\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>个人常用 Git 命令\",\"link\":\"/categories/fragments/2022/10/05/个人常用Git命令\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>个人常用 Docker 命令\",\"link\":\"/categories/fragments/2022/10/01/个人常用Docker命令\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>个人常用 SQL 函数\",\"link\":\"/categories/fragments/2022/02/16/个人常用SQL函数\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>个人常用 Linux 命令\",\"link\":\"/categories/fragments/2019/12/31/个人常用Linux命令\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">6</div>个人常用 Hutool 工具类\",\"link\":\"/categories/fragments/2019/12/30/个人常用Hutool工具类\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">7</div>个人常用 Stream 使用技巧\",\"link\":\"/categories/fragments/2019/12/29/个人常用Stream使用技巧\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">8</div>个人 SQL 优化技巧\",\"link\":\"/categories/fragments/2019/12/28/个人SQL优化技巧\"}],\"collapsed\":false},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/rabbit.svg\\\" title=\\\"兔年\\\" alt=\\\"生肖\\\">\\n 2023年 (2篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>一文详解限流接口实现\",\"link\":\"/categories/fragments/2023/12/21/一文详解限流接口实现\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>阿里巴巴的Code Review方法论与实践总结\",\"link\":\"/categories/fragments/2023/01/06/CodeReview方法论与实践总结\"}],\"collapsed\":false},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/tiger.svg\\\" title=\\\"虎年\\\" alt=\\\"生肖\\\">\\n 2022年 (15篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>简单聊聊如何让网站开启灰色显示\",\"link\":\"/categories/fragments/2022/12/07/网站开启灰色显示\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>使用 IntelliJ IDEA 进行远程程序调试\",\"link\":\"/categories/fragments/2022/11/01/使用IDEA进行远程程序调试\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>CentOS 安装 Docker、Docker Compose\",\"link\":\"/categories/fragments/2022/10/31/CentOS安装Docker\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>Docker 安装 MinIO 详细步骤\",\"link\":\"/categories/fragments/2022/10/28/Docker安装MinIO\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>Docker 安装 Consul 详细步骤\",\"link\":\"/categories/fragments/2022/10/27/Docker安装Consul\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">6</div>Docker 安装 OpenLDAP 详细步骤\",\"link\":\"/categories/fragments/2022/10/26/Docker安装OpenLDAP\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">7</div>个人常用快捷键\",\"link\":\"/categories/fragments/2022/10/06/个人常用快捷键\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">8</div>个人常用 Git 命令\",\"link\":\"/categories/fragments/2022/10/05/个人常用Git命令\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">9</div>个人常用 Docker 命令\",\"link\":\"/categories/fragments/2022/10/01/个人常用Docker命令\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">10</div>内网CentOS服务器设置网络代理\",\"link\":\"/categories/fragments/2022/08/29/内网CentOS服务器设置网络代理\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">11</div>为指定Git仓库单独配置用户名和邮箱\",\"link\":\"/categories/fragments/2022/03/28/为指定Git仓库单独配置用户名和邮箱\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">12</div>修改Git所有提交记录中的作者和邮箱\",\"link\":\"/categories/fragments/2022/03/27/修改Git所有提交记录中的作者和邮箱\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">13</div>修改Git最后一次提交记录的作者和邮箱\",\"link\":\"/categories/fragments/2022/03/26/修改Git最后一次提交记录的作者和邮箱\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">14</div>合并两个Git仓库的历史提交记录\",\"link\":\"/categories/fragments/2022/03/25/合并两个Git仓库的历史提交记录\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">15</div>个人常用 SQL 函数\",\"link\":\"/categories/fragments/2022/02/16/个人常用SQL函数\"}],\"collapsed\":true},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/ox.svg\\\" title=\\\"牛年\\\" alt=\\\"生肖\\\">\\n 2021年 (2篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>设计模式之单例模式\",\"link\":\"/categories/fragments/2021/05/29/设计模式之单例模式\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>精密计算工具类-BigDecimal\",\"link\":\"/categories/fragments/2021/03/12/精密计算工具类-BigDecimal\"}],\"collapsed\":true},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/pig.svg\\\" title=\\\"猪年\\\" alt=\\\"生肖\\\">\\n 2019年 (4篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>个人常用 Linux 命令\",\"link\":\"/categories/fragments/2019/12/31/个人常用Linux命令\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>个人常用 Hutool 工具类\",\"link\":\"/categories/fragments/2019/12/30/个人常用Hutool工具类\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>个人常用 Stream 使用技巧\",\"link\":\"/categories/fragments/2019/12/29/个人常用Stream使用技巧\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>个人 SQL 优化技巧\",\"link\":\"/categories/fragments/2019/12/28/个人SQL优化技巧\"}],\"collapsed\":true}],\"/categories/solutions/\":[{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/tiger.svg\\\" title=\\\"虎年\\\" alt=\\\"生肖\\\">\\n 2022年 (1篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>递归查询树型结构数据的性能优化方案\",\"link\":\"/categories/solutions/2022/09/07/递归查询树型结构数据的性能优化方案\"}],\"collapsed\":false},{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/ox.svg\\\" title=\\\"牛年\\\" alt=\\\"生肖\\\">\\n 2021年 (2篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>一条SQL查询今年每月统计信息\",\"link\":\"/categories/solutions/2021/11/22/一条SQL查询今年每月统计信息\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>用Java8获取近N天日期\",\"link\":\"/categories/solutions/2021/11/18/用Java8获取近N天日期\"}],\"collapsed\":true}],\"/categories/tools/\":[{\"text\":\"<img class=\\\"chinese-zodiac\\\" style=\\\"position: static; vertical-align: middle; padding-bottom: 3px;\\\" src=\\\"/img/svg/chinese-zodiac/ox.svg\\\" title=\\\"牛年\\\" alt=\\\"生肖\\\">\\n 2021年 (5篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>Quartz 快速入门\",\"link\":\"/categories/tools/2021/03/10/Quartz快速入门\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>Postman 快速入门\",\"link\":\"/categories/tools/2021/03/06/Postman快速入门\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>Another Redis Desktop Manager 快速入门\",\"link\":\"/categories/tools/2021/03/04/ARDM快速入门\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>Redis Desktop Manager 快速入门\",\"link\":\"/categories/tools/2021/02/22/RDM快速入门\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>初识 Lombok\",\"link\":\"/categories/tools/2021/01/14/初识Lombok\"}],\"collapsed\":false}],\"/courses/java/\":[{\"text\":\"Java语法入门 (14篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>开发环境搭建\",\"link\":\"/courses/java/01-Java语法入门/01-开发环境搭建\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>第一个Java程序\",\"link\":\"/courses/java/01-Java语法入门/02-第一个Java程序\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>初识Eclipse\",\"link\":\"/courses/java/01-Java语法入门/03-初识Eclipse\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>程序和计算机的那点事儿\",\"link\":\"/courses/java/01-Java语法入门/04-程序和计算机的那点事儿\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>变量和常量\",\"link\":\"/courses/java/01-Java语法入门/05-变量和常量\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">6</div>常用的运算符\",\"link\":\"/courses/java/01-Java语法入门/06-常用的运算符\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">7</div>控制语句和流程图\",\"link\":\"/courses/java/01-Java语法入门/07-控制语句和流程图\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">8</div>if选择结构\",\"link\":\"/courses/java/01-Java语法入门/08-if选择结构\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">9</div>switch选择结构\",\"link\":\"/courses/java/01-Java语法入门/09-switch选择结构\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">10</div>循环结构\",\"link\":\"/courses/java/01-Java语法入门/10-循环结构\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">11</div>多重循环\",\"link\":\"/courses/java/01-Java语法入门/11-多重循环\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">12</div>程序调试入门\",\"link\":\"/courses/java/01-Java语法入门/12-程序调试入门\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">13</div>一维数组\",\"link\":\"/courses/java/01-Java语法入门/13-一维数组\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">14</div>多维数组\",\"link\":\"/courses/java/01-Java语法入门/14-多维数组\"}],\"collapsed\":false},{\"text\":\"Java面向对象 (1篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>类和对象\",\"link\":\"/courses/java/02-Java面向对象/01-类和对象\"}],\"collapsed\":true},{\"text\":\"Java高级特性 (1篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>集合与泛型-1\",\"link\":\"/courses/java/03-Java高级特性/01-集合与泛型-1\"}],\"collapsed\":true},{\"text\":\"附录 (1篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>CentOS 8.2 安装 JDK 1.8.0_202\",\"link\":\"/courses/java/04-附录/01-CentOS安装JDK\"}],\"collapsed\":true}],\"/courses/mysql/\":[{\"text\":\"MySQL基础 (1篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>MySQL安装与配置\",\"link\":\"/courses/mysql/01-MySQL基础/01-MySQL安装与配置\"}],\"collapsed\":true},{\"text\":\"附录 (2篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>CentOS 8.2 安装 MySQL 5.7.39\",\"link\":\"/courses/mysql/03-附录/01-CentOS安装MySQL\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>Docker 安装 MySQL 详细步骤\",\"link\":\"/courses/mysql/03-附录/02-Docker安装MySQL\"}],\"collapsed\":false}],\"/courses/mybatis/\":[{\"text\":\"MyBatis基础 (8篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>快速入门\",\"link\":\"/courses/mybatis/01-MyBatis基础/01-快速入门\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>核心对象\",\"link\":\"/courses/mybatis/01-MyBatis基础/02-核心对象\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>核心配置文件\",\"link\":\"/courses/mybatis/01-MyBatis基础/03-核心配置文件\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>SQL映射文件之查询元素\",\"link\":\"/courses/mybatis/01-MyBatis基础/04-SQL映射文件之查询元素\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>SQL映射文件之增删改元素\",\"link\":\"/courses/mybatis/01-MyBatis基础/05-SQL映射文件之增删改元素\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">6</div>SQL映射文件之自定义映射元素\",\"link\":\"/courses/mybatis/01-MyBatis基础/06-SQL映射文件之自定义映射元素\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">7</div>SQL映射文件之缓存元素\",\"link\":\"/courses/mybatis/01-MyBatis基础/07-SQL映射文件之缓存元素\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">8</div>动态SQL\",\"link\":\"/courses/mybatis/01-MyBatis基础/08-动态SQL\"}],\"collapsed\":false},{\"text\":\"MyBatis-Plus基础 (5篇)\",\"items\":[{\"text\":\"<div class=\\\"text-color-red mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">1</div>快速入门\",\"link\":\"/courses/mybatis/02-MyBatis-Plus基础/01-快速入门\"},{\"text\":\"<div class=\\\"text-color-orange mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">2</div>增删改操作\",\"link\":\"/courses/mybatis/02-MyBatis-Plus基础/02-增删改操作\"},{\"text\":\"<div class=\\\"text-color-yellow mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">3</div>简单查询操作\",\"link\":\"/courses/mybatis/02-MyBatis-Plus基础/03-简单查询操作\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">4</div>条件构造器\",\"link\":\"/courses/mybatis/02-MyBatis-Plus基础/04-条件构造器\"},{\"text\":\"<div class=\\\"text-color-gray mr-[6px]\\\" style=\\\"font-weight: 550; display: inline-block;\\\">5</div>代码生成器\",\"link\":\"/courses/mybatis/02-MyBatis-Plus基础/05-代码生成器\"}],\"collapsed\":false}]},\"logo\":\"/logo.png\",\"outline\":{\"level\":\"deep\",\"label\":\"目录\"},\"darkModeSwitchLabel\":\"切换日光/暗黑模式\",\"sidebarMenuLabel\":\"文章\",\"returnToTopLabel\":\"返回顶部\",\"lastUpdatedText\":\"最后更新\",\"docFooter\":{\"prev\":\"上一篇\",\"next\":\"下一篇\"},\"editLink\":{\"pattern\":\"https://github.com/Charles7c/charles7c.github.io/edit/main/docs/:path\",\"text\":\"不妥之处，敬请雅正\"},\"search\":{\"provider\":\"algolia\",\"options\":{\"appId\":\"DBZ0G9HBUY\",\"apiKey\":\"00cef480a543003d05d9808110ea5f65\",\"indexName\":\"charles7c\",\"locales\":{\"root\":{\"placeholder\":\"搜索文档\",\"translations\":{\"button\":{\"buttonText\":\"搜索文档\",\"buttonAriaLabel\":\"搜索文档\"},\"modal\":{\"searchBox\":{\"resetButtonTitle\":\"清除查询条件\",\"resetButtonAriaLabel\":\"清除查询条件\",\"cancelButtonText\":\"取消\",\"cancelButtonAriaLabel\":\"取消\"},\"startScreen\":{\"recentSearchesTitle\":\"搜索历史\",\"noRecentSearchesText\":\"没有搜索历史\",\"saveRecentSearchButtonTitle\":\"保存至搜索历史\",\"removeRecentSearchButtonTitle\":\"从搜索历史中移除\",\"favoriteSearchesTitle\":\"收藏\",\"removeFavoriteSearchButtonTitle\":\"从收藏中移除\"},\"errorScreen\":{\"titleText\":\"无法获取结果\",\"helpText\":\"你可能需要检查你的网络连接\"},\"footer\":{\"selectText\":\"选择\",\"navigateText\":\"切换\",\"closeText\":\"关闭\",\"searchByText\":\"搜索提供者\"},\"noResultsScreen\":{\"noResultsText\":\"无法找到相关结果\",\"suggestedQueryText\":\"你可以尝试查询\",\"reportMissingResultsText\":\"你认为该查询应该有结果？\",\"reportMissingResultsLinkText\":\"点击反馈\"}}}}}}},\"socialLinks\":[{\"icon\":\"github\",\"link\":\"https://github.com/Charles7c/charles7c.github.io\"},{\"icon\":{\"svg\":\"<svg role=\\\"img\\\" viewBox=\\\"0 0 24 24\\\" xmlns=\\\"http://www.w3.org/2000/svg\\\"><title>码云</title><path d=\\\"M11.984 0A12 12 0 0 0 0 12a12 12 0 0 0 12 12 12 12 0 0 0 12-12A12 12 0 0 0 12 0a12 12 0 0 0-.016 0zm6.09 5.333c.328 0 .593.266.592.593v1.482a.594.594 0 0 1-.593.592H9.777c-.982 0-1.778.796-1.778 1.778v5.63c0 .327.266.592.593.592h5.63c.982 0 1.778-.796 1.778-1.778v-.296a.593.593 0 0 0-.592-.593h-4.15a.592.592 0 0 1-.592-.592v-1.482a.593.593 0 0 1 .593-.592h6.815c.327 0 .593.265.593.592v3.408a4 4 0 0 1-4 4H5.926a.593.593 0 0 1-.593-.593V9.778a4.444 4.444 0 0 1 4.445-4.444h8.296Z\\\"/></svg>\"},\"link\":\"https://gitee.com/Charles7c/charles7c\"},{\"icon\":{\"svg\":\"<svg width=\\\"33\\\" height=\\\"33\\\" xmlns=\\\"http://www.w3.org/2000/svg\\\" viewBox=\\\"0 0 174.8 204\\\">\\n <title>ContiNew Admin</title>\\n <path fill=\\\"#307AF2\\\" d=\\\"M86.7,0l88,51v.2l-16.3,9.4v-.2L86.7,18.9Zm71.8,143.5,16.3,9.4v.2L86.8,204h0l-16.3-9.4,16.3-9.4h0l71.7-41.5v-.2Z\\\"/>\\n <path fill=\\\"#12D2AC\\\" d=\\\"M16.3,143.5v.2L58,167.8l-16.3,9.4L0,153.1v-.2Z\\\"/>\\n <path fill=\\\"#12D2AC\\\" d=\\\"M104.1,93,15.9,143.8l-.2-.1V124.9l.2.1L87.7,83.6,104.1,93Z\\\"/>\\n <path fill=\\\"#0057FE\\\" d=\\\"M88.1,0,.1,51v.2l16.3,9.4v-.2L88.1,18.9Z\\\"/>\\n <path fill=\\\"#307AF2\\\" d=\\\"M.1,50.9.2,152.6l.2.1,16.3-9.4-.2-.1-.1-82.9L.1,50.9Z\\\"/>\\n <path fill=\\\"#0057FE\\\" d=\\\"M174.7,50.9l-.1,101.7-.2.1-16.3-9.4.2-.1.1-82.9Z\\\"/>\\n <path fill=\\\"#12D2AC\\\" d=\\\"M41.7,158.5l16.1,9.4,100.6-58.7V90.4Z\\\"/>\\n </svg>\"},\"link\":\"https://cnadmin.charles7c.top/\"}],\"articleMetadataConfig\":{\"author\":\"查尔斯\",\"authorLink\":\"/about/me\",\"showViewCount\":false},\"copyrightConfig\":{\"license\":\"署名-相同方式共享 4.0 国际 (CC BY-SA 4.0)\",\"licenseLink\":\"http://creativecommons.org/licenses/by-sa/4.0/\"},\"commentConfig\":{\"type\":\"gitalk\",\"showComment\":true},\"footerConfig\":{\"showFooter\":true,\"icpRecordCode\":\"津ICP备2022005864号-2\",\"publicSecurityRecordCode\":\"津公网安备12011202000677号\",\"copyright\":\"Copyright © 2019-2024 Charles7c\"}},\"locales\":{},\"scrollOffset\":90,\"cleanUrls\":true}");</script>
|
||
|
||
</body>
|
||
</html> |