<ul class="contains-task-list">
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox" checked=""> I have searched the <a href="https://github.com/apache/dubbo/issues">issues</a> of this repository and believe that this is not a duplicate.</li>
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox" checked=""> I have checked the <a href="https://github.com/apache/dubbo/blob/master/FAQ.md">FAQ</a> of this repository and believe that this is not a duplicate.</li>
</ul>
<h3 dir="auto">Environment</h3>
<ul dir="auto">
<li>Dubbo version: 2.7.6-SNAPSHOT</li>
</ul>
<div class="highlight highlight-source-java notranslate position-relative overflow-auto" dir="auto" data-snippet-clipboard-copy-content="  synchronized (parameterClassName.intern()) {
            CtClass ctClass = null;
            try {"><pre class="notranslate">  <span class="pl-k">synchronized</span> (<span class="pl-s1">parameterClassName</span>.<span class="pl-en">intern</span>()) {
            <span class="pl-smi">CtClass</span> <span class="pl-s1">ctClass</span> = <span class="pl-c1">null</span>;
            <span class="pl-k">try</span> {</pre></div>
<p dir="auto"><a href="https://github.com/apache/dubbo/blob/master/dubbo-filter/dubbo-filter-validation/src/main/java/org/apache/dubbo/validation/support/jvalidation/JValidator.java#L135">https://github.com/apache/dubbo/blob/master/dubbo-filter/dubbo-filter-validation/src/main/java/org/apache/dubbo/validation/support/jvalidation/JValidator.java#L135</a></p>
<blockquote>
<p dir="auto">Code should not synchronize on a variable or field of a boxed type (for example Integer, Boolean) or of type String since it is likely to contain an object that is used throughout the program. For example, Boolean.TRUE holds a single instance that will be used in many places throughout the program: whenever true is autoboxed or a call to Boolean.valueOf is made with true as an argument the same instance of Boolean is returned. It is therefore likely that two classes synchronizing on a field of type Boolean will end up synchronizing on the same object. This may lead to deadlock or threads being blocked unnecessarily.</p>
</blockquote>
<h3 dir="auto">References</h3>
<p dir="auto"><a href="https://wiki.sei.cmu.edu/confluence/display/java/LCK01-J.+Do+not+synchronize+on+objects+that+may+be+reused" rel="nofollow">https://wiki.sei.cmu.edu/confluence/display/java/LCK01-J.+Do+not+synchronize+on+objects+that+may+be+reused</a><br>
<a href="https://cwe.mitre.org/data/definitions/662.html" rel="nofollow">https://cwe.mitre.org/data/definitions/662.html</a></p>
<ul class="contains-task-list">
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox" checked=""> I have searched the <a href="https://github.com/apache/dubbo/issues">issues</a> of this repository and believe that this is not a duplicate.</li>
<li class="task-list-item"><input type="checkbox" id="" disabled="" class="task-list-item-checkbox" checked=""> I have checked the <a href="https://github.com/apache/dubbo/blob/master/FAQ.md">FAQ</a> of this repository and believe that this is not a duplicate.</li>
</ul>
<h3 dir="auto">Environment</h3>
<ul dir="auto">
<li>Dubbo version: 2.7.X</li>
<li>Operating System version: win10</li>
<li>Java version: 1.8</li>
</ul>
<h3 dir="auto">Steps to reproduce this issue</h3>
<ol dir="auto">
<li>dubbo method A B C on different dubbo server</li>
<li>A call B, B call C</li>
<li>In B MonitorFilter.MonitorListener.onResponse RpcContext.getContext().getRemoteHost() is null</li>
</ol>
<p dir="auto">Pls. provide [GitHub address] to reproduce this issue.</p>
<h3 dir="auto">Expected Result</h3>
<p dir="auto">RpcContext.getContext().getRemoteHost() is not null</p>
<h3 dir="auto">Actual Result</h3>
<p dir="auto">RpcContext.getContext().getRemoteHost() is null</p>
<p dir="auto"><a target="_blank" rel="noopener noreferrer nofollow" href="https://user-images.githubusercontent.com/6637227/68356710-00c1d000-014e-11ea-972a-db2bb4a75a3d.png"><img src="https://user-images.githubusercontent.com/6637227/68356710-00c1d000-014e-11ea-972a-db2bb4a75a3d.png" alt="image" style="max-width: 100%;"></a></p>