Site updated: 2024-11-29 11:28:36

Author: simuleite

ComputerScience/笔记/Web笔记/index.html

@@ -28,7 +28,7 @@
 <meta property="og:description" content="Tomcat  JRE报错 一般教程会让我们配置JAVA_HOME和JRE_HOME，然后启动Tomcat； 然而，在JDK9以后，就不默认包含JRE了。 此时，我们使用命令 jlink --module-path jmods --add-modules java.desktop --output jre 生成一个JRE后，启动Tomcat，就会报错： WARNING: Unknown modu">
 <meta property="og:locale" content="zh_CN">
 <meta property="article:published_time" content="2024-11-27T16:00:00.000Z">
-<meta property="article:modified_time" content="2024-11-28T02:36:02.369Z">
+<meta property="article:modified_time" content="2024-11-29T03:19:54.427Z">
 <meta property="article:author" content="SIMULEITE">
 <meta property="article:tag" content="笔记">
 <meta name="twitter:card" content="summary">
@@ -138,7 +138,7 @@
       <div class="sidebar-panel-container">
         <!--noindex-->
         <div class="post-toc-wrap sidebar-panel">
-            <div class="post-toc animated"><ol class="nav"><li class="nav-item nav-level-1"><a class="nav-link" href="#tomcat"><span class="nav-text"> Tomcat</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#jre%E6%8A%A5%E9%94%99"><span class="nav-text"> JRE报错</span></a></li></ol></li><li class="nav-item nav-level-1"><a class="nav-link" href="#cookies"><span class="nav-text"> Cookies</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#remember-me"><span class="nav-text"> Remember-me</span></a></li><li class="nav-item nav-level-2"><a class="nav-link" href="#session"><span class="nav-text"> Session</span></a></li></ol></li><li class="nav-item nav-level-1"><a class="nav-link" href="#servlet"><span class="nav-text"> Servlet</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#%E4%B8%8A%E4%BC%A0%E6%96%87%E4%BB%B6"><span class="nav-text"> 上传文件</span></a></li></ol></li></ol></div>
+            <div class="post-toc animated"><ol class="nav"><li class="nav-item nav-level-1"><a class="nav-link" href="#tomcat"><span class="nav-text"> Tomcat</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#jre%E6%8A%A5%E9%94%99"><span class="nav-text"> JRE报错</span></a></li></ol></li><li class="nav-item nav-level-1"><a class="nav-link" href="#cookies"><span class="nav-text"> Cookies</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#remember-me"><span class="nav-text"> Remember-me</span></a></li><li class="nav-item nav-level-2"><a class="nav-link" href="#session"><span class="nav-text"> Session</span></a></li></ol></li><li class="nav-item nav-level-1"><a class="nav-link" href="#servlet"><span class="nav-text"> Servlet</span></a><ol class="nav-child"><li class="nav-item nav-level-2"><a class="nav-link" href="#%E4%B8%8A%E4%BC%A0%E6%96%87%E4%BB%B6"><span class="nav-text"> 上传文件</span></a></li><li class="nav-item nav-level-2"><a class="nav-link" href="#context"><span class="nav-text"> Context</span></a></li></ol></li><li class="nav-item nav-level-1"><a class="nav-link" href="#filter"><span class="nav-text"> Filter</span></a></li></ol></div>
         </div>
         <!--/noindex-->
 
@@ -223,9 +223,15 @@ <h1 class="post-title" itemprop="name headline">
         <i class="far fa-calendar"></i>
       </span>
       <span class="post-meta-item-text">发表于</span>
-      
 
-      <time title="创建时间：2024-11-28 00:00:00 / 修改时间：10:36:02" itemprop="dateCreated datePublished" datetime="2024-11-28T00:00:00+08:00">2024-11-28</time>
+      <time title="创建时间：2024-11-28 00:00:00" itemprop="dateCreated datePublished" datetime="2024-11-28T00:00:00+08:00">2024-11-28</time>
+    </span>
+    <span class="post-meta-item">
+      <span class="post-meta-item-icon">
+        <i class="far fa-calendar-check"></i>
+      </span>
+      <span class="post-meta-item-text">更新于</span>
+      <time title="修改时间：2024-11-29 11:19:54" itemprop="dateModified" datetime="2024-11-29T11:19:54+08:00">2024-11-29</time>
     </span>
 
 
@@ -246,6 +252,7 @@ <h2 id="jre报错"><a class="markdownIt-Anchor" href="#jre报错"></a> JRE报错
 <p>生成一个JRE后，启动Tomcat，就会报错：</p>
 <figure class="highlight shell"><table><tr><td class="code"><pre><span class="line">WARNING: Unknown module: java.rmi specified to --add-opens</span><br><span class="line">Exception in thread &quot;main&quot; java.lang.NoClassDefFoundError: java/util/logging/Logger</span><br><span class="line">    at org.apache.juli.logging.DirectJDKLog.&lt;init&gt;(DirectJDKLog.java:61)</span><br><span class="line">    at org.apache.juli.logging.DirectJDKLog.getInstance(DirectJDKLog.java:181)</span><br><span class="line">    at org.apache.juli.logging.LogFactory.getInstance(LogFactory.java:133)</span><br><span class="line">    at org.apache.juli.logging.LogFactory.getInstance(LogFactory.java:156)</span><br><span class="line">    at org.apache.juli.logging.LogFactory.getLog(LogFactory.java:211)</span><br><span class="line">    at org.apache.catalina.startup.Bootstrap.&lt;clinit&gt;(Bootstrap.java:49)</span><br><span class="line">Caused by: java.lang.ClassNotFoundException: java.util.logging.Logger</span><br><span class="line">    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)</span><br><span class="line">    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)</span><br><span class="line">    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:525)</span><br><span class="line">    ... 6 more</span><br></pre></td></tr></table></figure>
 <p>这时候，只需要把jre文件和<code>JRE_HOME</code>环境变量删除，Tomcat就能正常启动</p>
+<span id="more"></span>
 <h1 id="cookies"><a class="markdownIt-Anchor" href="#cookies"></a> Cookies</h1>
 <h2 id="remember-me"><a class="markdownIt-Anchor" href="#remember-me"></a> Remember-me</h2>
 <figure class="highlight html"><table><tr><td class="code"><pre><span class="line"><span class="tag">&lt;<span class="name">div</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">label</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;<span class="name">input</span> <span class="attr">type</span>=<span class="string">&quot;checkbox&quot;</span> <span class="attr">placeholder</span>=<span class="string">&quot;记住密码&quot;</span> <span class="attr">name</span>=<span class="string">&quot;remember-me&quot;</span>&gt;</span></span><br><span class="line">        记住密码</span><br><span class="line">    <span class="tag">&lt;/<span class="name">label</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">div</span>&gt;</span></span><br></pre></td></tr></table></figure>
@@ -276,6 +283,17 @@ <h2 id="上传文件"><a class="markdownIt-Anchor" href="#上传文件"></a> 上
 <figure class="highlight html"><table><tr><td class="code"><pre><span class="line"><span class="comment">&lt;!-- multipart 传文件 --&gt;</span></span><br><span class="line"><span class="tag">&lt;<span class="name">form</span> <span class="attr">method</span>=<span class="string">&quot;post&quot;</span> <span class="attr">action</span>=<span class="string">&quot;file&quot;</span> <span class="attr">enctype</span>=<span class="string">&quot;multipart/form-data&quot;</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">div</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;<span class="name">input</span> <span class="attr">type</span>=<span class="string">&quot;file&quot;</span> <span class="attr">name</span>=<span class="string">&quot;test-file&quot;</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">div</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;<span class="name">div</span>&gt;</span></span><br><span class="line">        <span class="tag">&lt;<span class="name">button</span>&gt;</span>上传文件<span class="tag">&lt;/<span class="name">button</span>&gt;</span></span><br><span class="line">    <span class="tag">&lt;/<span class="name">div</span>&gt;</span></span><br><span class="line"><span class="tag">&lt;/<span class="name">form</span>&gt;</span></span><br></pre></td></tr></table></figure>
 <p>后端定义Post方法</p>
 <figure class="highlight java"><table><tr><td class="code"><pre><span class="line"><span class="meta">@MultipartConfig</span> <span class="comment">// 文件传输注解</span></span><br><span class="line"><span class="meta">@WebServlet(&quot;/file&quot;)</span></span><br><span class="line"><span class="keyword">public</span> <span class="keyword">class</span> <span class="title class_">FileServlet</span> <span class="keyword">extends</span> <span class="title class_">HttpServlet</span> &#123;</span><br><span class="line"></span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="keyword">protected</span> <span class="keyword">void</span> <span class="title function_">doPost</span><span class="params">(HttpServletRequest req, HttpServletResponse resp)</span> <span class="keyword">throws</span> ServletException, IOException &#123;</span><br><span class="line">        <span class="keyword">try</span>(<span class="type">FileOutputStream</span> <span class="variable">stream</span> <span class="operator">=</span> <span class="keyword">new</span> <span class="title class_">FileOutputStream</span>(<span class="string">&quot;/Users/nagocoler/Documents/IdeaProjects/WebTest/test.png&quot;</span>))&#123;</span><br><span class="line">            <span class="type">Part</span> <span class="variable">part</span> <span class="operator">=</span> req.getPart(<span class="string">&quot;test-file&quot;</span>);</span><br><span class="line">            IOUtils.copy(part.getInputStream(), stream);</span><br><span class="line">            resp.setContentType(<span class="string">&quot;text/html;charset=UTF-8&quot;</span>);</span><br><span class="line">            resp.getWriter().write(<span class="string">&quot;文件上传成功！&quot;</span>);</span><br><span class="line">        &#125;</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
+<h2 id="context"><a class="markdownIt-Anchor" href="#context"></a> Context</h2>
+<blockquote>
+<p>ServeletContext属于整个Web应用程序，全局唯一</p>
+</blockquote>
+<figure class="highlight java"><table><tr><td class="code"><pre><span class="line"><span class="type">ServeltContext</span> <span class="variable">context</span> <span class="operator">=</span> getServletContext();</span><br><span class="line">context.setAttribute(<span class="string">&quot;key&quot;</span>, <span class="string">&quot;value&quot;</span>);</span><br></pre></td></tr></table></figure>
+<h1 id="filter"><a class="markdownIt-Anchor" href="#filter"></a> Filter</h1>
+<blockquote>
+<p>Filter相当于在所有访问前加了一堵墙，来自浏览器的所有访问请求都会首先经过Filter。</p>
+</blockquote>
+<p>只有Filter允许通过的请求，才可以顺利到达Servlet。</p>
+<figure class="highlight java"><table><tr><td class="code"><pre><span class="line"><span class="meta">@WebFileter(&quot;/*&quot;)</span></span><br><span class="line"><span class="keyword">public</span> <span class="keyword">class</span> <span class="title class_">MyFilter</span> <span class="keyword">implements</span> <span class="title class_">Filter</span> &#123;</span><br><span class="line">    <span class="meta">@Override</span></span><br><span class="line">    <span class="keyword">public</span> <span class="keyword">void</span> <span class="title function_">doFilter</span><span class="params">(req, resp, chain)</span> &#123;</span><br><span class="line">        ...</span><br><span class="line">        chain.doFilter(req, res);</span><br><span class="line">    &#125;</span><br><span class="line">&#125;</span><br></pre></td></tr></table></figure>
     </div>