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<li class="toctree-l2 current"><a class="current reference internal" href="#">classloader</a><ul>
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<li class="toctree-l4"><a class="reference internal" href="#use-the-classloader-to-load-class">Use the classloader to load class</a></li>
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<div class="section" id="classloader">
<h1>classloader<a class="headerlink" href="#classloader" title="Permalink to this headline">¶</a></h1>
<p>View hierarchy, urls and classes-loading info for the class-loaders.</p>
<p><code class="docutils literal notranslate"><span class="pre">classloader</span></code> can search and print out the URLs for a specified resource from one particular classloader. It is quite handy when analyze <code class="docutils literal notranslate"><span class="pre">ResourceNotFoundException</span></code>.</p>
<div class="section" id="options">
<h2>Options<a class="headerlink" href="#options" title="Permalink to this headline">¶</a></h2>
<table border="1" class="docutils">
<thead>
<tr>
<th align="right">Name</th>
<th align="left">Specification</th>
</tr>
</thead>
<tbody>
<tr>
<td align="right">[l]</td>
<td align="left">list all classloader instances</td>
</tr>
<tr>
<td align="right">[t]</td>
<td align="left">print classloader's hierarchy</td>
</tr>
<tr>
<td align="right">[a]</td>
<td align="left">list all the classes loaded by all the classloaders (use it with great caution since the output can be huge)</td>
</tr>
<tr>
<td align="right">[c:]</td>
<td align="left">print classloader's hashcode</td>
</tr>
<tr>
<td align="right"><code>[c: r:]</code></td>
<td align="left">using ClassLoader to search resource</td>
</tr>
<tr>
<td align="right"><code>[c: load:]</code></td>
<td align="left">using ClassLoader to load class</td>
</tr>
</tbody>
</table></div>
<div class="section" id="usage">
<h2>Usage<a class="headerlink" href="#usage" title="Permalink to this headline">¶</a></h2>
<div class="section" id="view-statistics-categorized-by-class-type">
<h3>View statistics categorized by class type<a class="headerlink" href="#view-statistics-categorized-by-class-type" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader
name numberOfInstances loadedCountTotal
com.taobao.arthas.agent.ArthasClassloader 1 2115
BootstrapClassLoader 1 1861
sun.reflect.DelegatingClassLoader 5 5
sun.misc.Launcher$AppClassLoader 1 4
sun.misc.Launcher$ExtClassLoader 1 1
Affect(row-cnt:5) cost in 3 ms.</pre></div>
</div>
</div>
<div class="section" id="view-statistics-categorized-by-loaded-classes-number">
<h3>View statistics categorized by loaded classes number<a class="headerlink" href="#view-statistics-categorized-by-loaded-classes-number" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader -l
name loadedCount hash parent
BootstrapClassLoader 1861 null null
com.taobao.arthas.agent.ArthasClassloader@68b31f0a 2115 68b31f0a sun.misc.Launcher$ExtClassLoader@66350f69
sun.misc.Launcher$AppClassLoader@3d4eac69 4 3d4eac69 sun.misc.Launcher$ExtClassLoader@66350f69
sun.misc.Launcher$ExtClassLoader@66350f69 1 66350f69 null
Affect(row-cnt:4) cost in 2 ms.</pre></div>
</div>
</div>
<div class="section" id="view-class-loaders-hierarchy">
<h3>View class-loaders hierarchy<a class="headerlink" href="#view-class-loaders-hierarchy" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader -t
+-BootstrapClassLoader
+-sun.misc.Launcher$ExtClassLoader@66350f69
+-com.taobao.arthas.agent.ArthasClassloader@68b31f0a
+-sun.misc.Launcher$AppClassLoader@3d4eac69
Affect(row-cnt:4) cost in 3 ms.</pre></div>
</div>
</div>
<div class="section" id="show-the-urls-of-the-urlclassloader">
<h3>Show the URLs of the URLClassLoader<a class="headerlink" href="#show-the-urls-of-the-urlclassloader" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader -c 3d4eac69
file:/private/tmp/arthas-demo.jar
file:/Users/hengyunabc/.arthas/lib/3.0.5/arthas/arthas-agent.jar
Affect(row-cnt:9) cost in 3 ms.</pre></div>
</div>
</div>
<div class="section" id="use-the-classloader-to-load-resource">
<h3>Use the classloader to load resource<a class="headerlink" href="#use-the-classloader-to-load-resource" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader -c 3d4eac69 -r META-INF/MANIFEST.MF
jar:file:/System/Library/Java/Extensions/MRJToolkit.jar!/META-INF/MANIFEST.MF
jar:file:/private/tmp/arthas-demo.jar!/META-INF/MANIFEST.MF
jar:file:/Users/hengyunabc/.arthas/lib/3.0.5/arthas/arthas-agent.jar!/META-INF/MANIFEST.MF</pre></div>
</div>
<p>Use the classloader to load <code class="docutils literal notranslate"><span class="pre">.class</span></code> resource</p>
<div class="highlight-shell notranslate"><div class="highlight hljs"><pre class="shell">$ classloader -c 1b6d3586 -r java/lang/String.class
jar:file:/Library/Java/JavaVirtualMachines/jdk1.8.0_60.jdk/Contents/Home/jre/lib/rt.jar!/java/lang/String.class</pre></div>
</div>
</div>
<div class="section" id="use-the-classloader-to-load-class">
<h3>Use the classloader to load class<a class="headerlink" href="#use-the-classloader-to-load-class" title="Permalink to this headline">¶</a></h3>
<div class="highlight-bash notranslate"><div class="highlight hljs"><pre class="bash">$ classloader -c 3d4eac69 --load demo.MathGame
load class success.
class-info demo.MathGame
code-source /private/tmp/arthas-demo.jar
name demo.MathGame
isInterface false
isAnnotation false
isEnum false
isAnonymousClass false
isArray false
isLocalClass false
isMemberClass false
isPrimitive false
isSynthetic false
simple-name MathGame
modifier public
annotation
interfaces
super-class +-java.lang.Object
class-loader +-sun.misc.Launcher$AppClassLoader@3d4eac69
+-sun.misc.Launcher$ExtClassLoader@66350f69
classLoaderHash 3d4eac69</pre></div>
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