Debugging into Java core libraries with Eclipse

  1. Unzip the jdk src.zip file
  2. Create a project and build the java source
  3. Open the Eclipse project run dialog for the project you want to debug into the java source from
  4. Click on the Classpath tab
  5. Click on the Bootstrap Entries
  6. Click the Add Projects button
  7. Add the java source project
  8. Click on the Up/Down buttons to move the java source project above the JRE System Library (equivalent to -Xbootclasspath/p)
  9. Debug your project as normal and you will be able inspect variables as you step through the java core libraries
  10. Alter the java source to add instrumentation for things like recording last mutator thread stack trace of Collections for debugging and discovering the source of ConcurrentModificationException, etc.

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