[FIXED] Internal error during "Initialize Java Debug Session" on Eclipse

Issue

I'm using Eclipse 2020-09, jdk-15, jre1.8.0_271. When I try to launch a debug client, Eclipse throws the below error at me:

   An internal error occurred during: "Initialize Java Debug Session".
Expecting a stackmap frame at branch target 12
Exception Details:
  Location:
    org/eclipse/jdt/internal/debug/core/model/JDIStackFrame.equals(Ljava/lang/Object;Ljava/lang/Object;)Z @1: ifnonnull
  Reason:
    Expected stackmap frame at this location.
  Bytecode:
    0000000: 2bc7 000b 2cc7 0005 04ac 03ac 2b2c b600
    0000010: c1ac                                   

Instead of showing the variable status and letting me step through/into the breakpoint I've set, it simply runs the code up to the breakpoint and then stops. It's a fresh installation of eclipse on a recently wiped machine, so I am rather at a loss. I've checked the JAVA_HOME env variable, the path variable, the eclipse.ini file, and probably some other things that I'm forgetting now.

Solution

Well, turns out I forgot that I installed a kotlin plugin (https://marketplace.eclipse.org/content/kotlin-plugin-eclipse) on eclipse and that was evidently breaking it. Seems to have just been an odd bug in the plugin, as removing it restored full functionality.

Answered By - MangoPicante
Answer Checked By - Mildred Charles (JavaFixing Admin)