title: Why am I getting sun.misc.Contended symbol cannot find error?
body: <p>I've got a very simple program:</p>
  
  <p><code>Test.java</code>:</p>
  
  <pre><code>package com;
  import sun.misc.Contended;
  public class Test {
  }
  </code></pre>
  
  <p>and <code>pom.xml</code></p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;project xmlns="http://maven.apache.org/POM/4.0.0"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://maven.apache.org/POM/4.0.0                              http://maven.apache.org/xsd/maven-4.0.0.xsd"&gt;
  &lt;modelVersion&gt;4.0.0&lt;/modelVersion&gt;
  
  &lt;groupId&gt;com&lt;/groupId&gt;
  &lt;artifactId&gt;Test&lt;/artifactId&gt;
  &lt;version&gt;1.0-SNAPSHOT&lt;/version&gt;
  
  &lt;properties&gt;
      &lt;maven.compiler.source&gt;1.9&lt;/maven.compiler.source&gt;
      &lt;maven.compiler.target&gt;1.9&lt;/maven.compiler.target&gt;
  &lt;/properties&gt;
  &lt;/project&gt;
  </code></pre>
  
  <p>when I put <code>mvn compile</code> I've got: </p>
  
  <pre><code>[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.2:compile (default-compile) on project proj: Compilation failure
  [ERROR] /home/john/Desktop/proj/src/main/java/com/Test.java: cannot find symbol
  [ERROR] symbol:   class Contended
  [ERROR] location: package sun.misc
  </code></pre>
  
  <p>Why?</p>