title: If a source code is not inside JDK's src.zip, does it mean it's not open source?
body: <p>I want to see the source code of sun.nio.ch.SocketChannelImpl#read function. But there's no corresponding source in src.zip of Oracle's JDK.  </p>
  
  <p>I know I can see it from the OpenJDK's openjdk-6-src-b27-26_oct_2012.tar.gz downloaded from <a href="http://download.java.net/openjdk/jdk6/" rel="nofollow">http://download.java.net/openjdk/jdk6/</a>.  </p>
  
  <p>But does it mean that I can't get it from the more popular non-open JDK because it's not open source? Or I'm missing something and I actually can get it from Oracle JDK?(I don't know much of the difference of JDK and OpenJDK)  </p>
  
  <hr>
  
  <p>Update:<br>
  I don't understand why Oracle didn't include all the sources in src.zip since one can get it from OpenJDK. What do they want to hide? I think if any source if not in the src.zip, it means that Oracle use "some closed source third party components" or "commercial features" for that. Right?  </p>
  
  <p>Quote from <a href="https://blogs.oracle.com/henrik/entry/java_7_questions_answers" rel="nofollow">https://blogs.oracle.com/henrik/entry/java_7_questions_answers</a>:</p>
  
  <blockquote>
    <p>" Q: Where can I find the source code? A: The source code for the Java
    SE 7 Reference Implementation is available from the JDK 7 Project in
    the OpenJDK Community.</p>
    
    <p>Q: What is the difference between the source code found in the OpenJDK
    repository, and the code you use to build the Oracle JDK?    A: It is
    very close - our build process for Oracle JDK releases builds on
    OpenJDK 7 by adding just a couple of pieces, like the deployment code,
    which includes Oracle's implementation of the Java Plugin and Java
    WebStart, as well as some closed source third party components like a
    graphics rasterizer, some open source third party components, like
    Rhino, and a few bits and pieces here and there, like additional
    documentation or third party fonts. Moving forward, our intent is to
    open source all pieces of the Oracle JDK except those that we consider
    commercial features such as JRockit Mission Control (not yet available
    in Oracle JDK), and replace encumbered third party components with
    open source alternatives to achieve closer parity between the code
    bases."</p>
  </blockquote>