The JDK source code is packaged in a src.jar, and should be in the JDK/Home folder. However, some JDK versions in Mac OSX didn’t include the source code or Javadoc.
The JDK source code is inside the src.zip, this article shows you how to get it on Windows, Ubuntu (Linux) and Mac OSX.
Deployed a Debian 7.5 on Linode server, the default is using OpenJDK 1.6. How to upgrade to OpenJDK 1.7?
The current environment is using Tomcat 7 + JDK 6. How to configure Tomcat to use JDK 7?
In Java, we can use javap -verbose className to print out the class information.