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class="post-header"> <h1 class="post-title-main">Error Prone</h1> </div> <div class="post-content" data-github-edit-url="https://github.com/pmd/pmd/blob/main/docs/../pmd-jsp/src/main/resources/category/jsp/errorprone.xml"> <div class="summary">Rules to detect constructs that are either broken, extremely confusing or prone to runtime errors.</div> <details id="inline-toc-details"> <summary>Table of Contents</summary> <div id="inline-toc"><!-- empty, move TOC here when screen size too small --></div> </details> <!-- DO NOT EDIT THIS FILE. This file is generated from file ../pmd-jsp/src/main/resources/category/jsp/errorprone.xml. --> <h2 id="jspencoding">JspEncoding</h2> <p><strong>Since:</strong> PMD 4.0</p> <p><strong>Priority:</strong> Medium (3)</p> <p>A missing ‘meta’ tag or page directive will trigger this rule, as well as a non-UTF-8 charset.</p> <p><strong>This rule is defined by the following XPath expression:</strong></p> <div class="language-xpath highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="o">//</span><span class="nt">CompilationUnit</span><span class="o">/</span><span class="nt">Content</span><span class="p">[</span><span class="w"> </span><span class="ow">not</span><span class="p">(</span><span class="nt">Element</span><span class="p">[</span><span class="na">@Name</span><span class="err">=</span><span class="s2">"meta"</span><span class="p">][</span><span class="w"> </span><span class="nt">Attribute</span><span class="p">[</span><span class="na">@Name</span><span class="err">=</span><span class="s2">"content"</span><span class="p">]</span><span class="o">/</span><span class="nt">AttributeValue</span><span class="p">[</span><span class="nf">contains</span><span class="p">(</span><span class="nf">lower-case</span><span class="p">(</span><span class="na">@Value</span><span class="p">),</span><span class="s2">"charset=utf-8"</span><span class="p">)]</span><span class="w"> </span><span class="p">])</span><span class="w"> </span><span class="ow">and</span><span class="w"> </span><span class="ow">not</span><span class="p">(</span><span class="nt">JspDirective</span><span class="p">[</span><span class="na">@Name</span><span class="err">=</span><span class="s1">'page'</span><span class="p">]</span><span class="o">/</span><span class="nt">JspDirectiveAttribute</span><span class="p">[</span><span class="na">@Name</span><span class="err">=</span><span class="s1">'contentType'</span><span class="p">][</span><span class="nf">contains</span><span class="p">(</span><span class="nf">lower-case</span><span class="p">(</span><span class="na">@Value</span><span class="p">),</span><span class="s2">"charset=utf-8"</span><span class="p">)])</span><span class="w"> </span><span class="p">]</span><span class="w"> </span></code></pre></div></div> <p><strong>Example(s):</strong></p> <div class="language-jsp highlighter-rouge"><div class="highlight"><pre class="highlight"><code>Most browsers should be able to interpret the following headers: <span class="nt"><%@ page </span><span class="na">contentType=</span><span class="s">"text/html; charset=UTF-8"</span><span class="na"> pageEncoding=</span><span class="s">"UTF-8"</span> <span class="nt">%></span> <span class="nt"><meta</span> <span class="na">http-equiv=</span><span class="s">"Content-Type"</span><span class="err"> </span> <span class="na">content=</span><span class="s">"text/html; charset=UTF-8"</span> <span class="nt">/></span> </code></pre></div></div> <p><strong>Use this rule by referencing it:</strong></p> <div class="language-xml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="nt"><rule</span> <span class="na">ref=</span><span class="s">"category/jsp/errorprone.xml/JspEncoding"</span> <span class="nt">/></span> </code></pre></div></div> <div class="tags"> </div> </div> <footer> <hr /> <div> This documentation is written in markdown. <br /> If there is something missing or can be improved, edit this page on github and create a PR: <a target="_blank" href="https://github.com/pmd/pmd/blob/main/docs/../pmd-jsp/src/main/resources/category/jsp/errorprone.xml" role="button" ><i class="fab fa-github fa-lg"></i> Edit on GitHub</a > </div> <hr /> <div class="row"> <div class="col-lg-12 footer"> ©2024 PMD Open Source Project. 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