Is JVM open source code?

by

It depends entirely on which JVM you use.

If you use the OpenJDK JVM, then you can get the source code from here.
If you use the Kaffe JVM, you can get the source from here.
If you use the Sun JVM version 6 or later, then you can get the source from here.

If you use a Sun JVM earlier than 6, then you can often get the source under an academic license. If you use an IBM, Oracle, HP, or other JVM, then the source is not open.

Update May 2013

The Version 6 source can still be accessed by the above link, or it can be accessed via this link. This latter link also includes a handy genealogy table that shows how the Oracle JDK and OpenJDK versions match with each other.

Additionally, a more up to date version of the Java 7 source can be found here. This also includes the fixes for the releases of Java 7 since GA.

And, of no surprise to anyone, the Java 8 sources can be found here.

More Related Contents:

  1. What are the -Xms and -Xmx parameters when starting JVM?
  2. PermGen elimination in JDK 8
  3. Why would you ever implement finalize()?
  4. Android Studio Gradle project “Unable to start the daemon process /initialization of VM”
  5. Can Java 8 code be compiled to run on Java 7 JVM?
  6. Difference between thread’s context class loader and normal classloader
  7. Java heap terminology: young, old and permanent generations?
  8. Difference between _JAVA_OPTIONS, JAVA_TOOL_OPTIONS and JAVA_OPTS
  9. Java 32-bit vs 64-bit compatibility
  10. Debug a java application without starting the JVM with debug arguments
  11. When is the static block of a class executed?
  12. java.lang.OutOfMemoryError: PermGen space [closed]
  13. Find out what JVM Eclipse is running on
  14. Exception 0xC0000005 from JNI_CreateJavaVM (jvm.dll)
  15. Why are Java 8 lambdas invoked using invokedynamic?
  16. Bytecode features not available in the Java language
  17. What makes hot deployment a “hard problem”?
  18. Java verbose class loading
  19. Why have one JVM per application?
  20. Why doesn’t the JVM cache JIT compiled code?
  21. What are bytecodes and how does the JVM handle them
  22. Why a sawtooth shaped graph?
  23. If I compiled a Java file with the newest JDK, would an older JVM be able to run the .class files?
  24. Java for-loop optimization
  25. Specifying JVM arguments when calling a jar file?
  26. how to increase java heap memory permanently?
  27. How can I add a Javaagent to a JVM without stopping the JVM?
  28. Java Memory explained (SUN JVM)
  29. how to choose the jvm heap size?
  30. Trick behind JVM’s compressed Oops

Leave a Comment