https://www.graalvm.org/ 
class com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread extends java.lang.Thread
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread
  super_class: java.lang.Thread
{
  private final org.graalvm.polyglot.Engine engine;
    descriptor: Lorg/graalvm/polyglot/Engine;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final com.oracle.truffle.api.instrumentation.TruffleInstrument$Env env;
    descriptor: Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private java.util.Iterator<java.util.concurrent.CountDownLatch> executionLatches;
    descriptor: Ljava/util/Iterator;
    flags: (0x0002) ACC_PRIVATE
    Signature: Ljava/util/Iterator<Ljava/util/concurrent/CountDownLatch;>;

  final com.oracle.truffle.api.instrumentation.test.GR25718Test this$0;
    descriptor: Lcom/oracle/truffle/api/instrumentation/test/GR25718Test;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.api.instrumentation.test.GR25718Test, org.graalvm.polyglot.Engine, com.oracle.truffle.api.instrumentation.TruffleInstrument$Env);
    descriptor: (Lcom/oracle/truffle/api/instrumentation/test/GR25718Test;Lorg/graalvm/polyglot/Engine;Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=4, args_size=4
        start local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
        start local 2 // org.graalvm.polyglot.Engine engine
        start local 3 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env env
         0: .line 120
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.this$0:Lcom/oracle/truffle/api/instrumentation/test/GR25718Test;
         1: .line 121
            aload 0 /* this */
            ldc "Instrumentation Thread"
            invokespecial java.lang.Thread.<init>:(Ljava/lang/String;)V
         2: .line 122
            aload 0 /* this */
            aload 2 /* engine */
            putfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.engine:Lorg/graalvm/polyglot/Engine;
         3: .line 123
            aload 0 /* this */
            aload 3 /* env */
            putfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.env:Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;
         4: .line 124
            return
        end local 3 // com.oracle.truffle.api.instrumentation.TruffleInstrument$Env env
        end local 2 // org.graalvm.polyglot.Engine engine
        end local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    5     0    this  Lcom/oracle/truffle/api/instrumentation/test/GR25718Test$InstrumentationThread;
            0    5     2  engine  Lorg/graalvm/polyglot/Engine;
            0    5     3     env  Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;
    MethodParameters:
        Name  Flags
      this$0  final
      engine  
      env     

  void setExecutionLatches(java.util.List<java.util.concurrent.CountDownLatch>);
    descriptor: (Ljava/util/List;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
        start local 1 // java.util.List latches
         0: .line 127
            aload 0 /* this */
            aload 1 /* latches */
            invokeinterface java.util.List.iterator:()Ljava/util/Iterator;
            putfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.executionLatches:Ljava/util/Iterator;
         1: .line 128
            return
        end local 1 // java.util.List latches
        end local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    2     0     this  Lcom/oracle/truffle/api/instrumentation/test/GR25718Test$InstrumentationThread;
            0    2     1  latches  Ljava/util/List<Ljava/util/concurrent/CountDownLatch;>;
    Signature: (Ljava/util/List<Ljava/util/concurrent/CountDownLatch;>;)V
    MethodParameters:
         Name  Flags
      latches  

  public void run();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=8, locals=4, args_size=1
        start local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
         0: .line 132
            aconst_null
            astore 1
            aconst_null
            astore 2
         1: iconst_0
            anewarray java.lang.String
            invokestatic org.graalvm.polyglot.Context.newBuilder:([Ljava/lang/String;)Lorg/graalvm/polyglot/Context$Builder;
            aload 0 /* this */
            getfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.engine:Lorg/graalvm/polyglot/Engine;
            invokevirtual org.graalvm.polyglot.Context$Builder.engine:(Lorg/graalvm/polyglot/Engine;)Lorg/graalvm/polyglot/Context$Builder;
            invokevirtual org.graalvm.polyglot.Context$Builder.build:()Lorg/graalvm/polyglot/Context;
            astore 3 /* c */
        start local 3 // org.graalvm.polyglot.Context c
         2: .line 133
            aload 3 /* c */
            ldc "proxyLanguage"
            ldc "getExecLatches"
            invokevirtual org.graalvm.polyglot.Context.eval:(Ljava/lang/String;Ljava/lang/CharSequence;)Lorg/graalvm/polyglot/Value;
            pop
         3: .line 134
            aload 3 /* c */
            ifnull 9
            aload 3 /* c */
            invokevirtual org.graalvm.polyglot.Context.close:()V
            goto 9
      StackMap locals: com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread java.lang.Throwable java.lang.Throwable org.graalvm.polyglot.Context
      StackMap stack: java.lang.Throwable
         4: astore 1
            aload 3 /* c */
            ifnull 5
            aload 3 /* c */
            invokevirtual org.graalvm.polyglot.Context.close:()V
        end local 3 // org.graalvm.polyglot.Context c
      StackMap locals:
      StackMap stack:
         5: aload 1
            athrow
      StackMap locals:
      StackMap stack: java.lang.Throwable
         6: astore 2
            aload 1
            ifnonnull 7
            aload 2
            astore 1
            goto 8
      StackMap locals:
      StackMap stack:
         7: aload 1
            aload 2
            if_acmpeq 8
            aload 1
            aload 2
            invokevirtual java.lang.Throwable.addSuppressed:(Ljava/lang/Throwable;)V
      StackMap locals:
      StackMap stack:
         8: aload 1
            athrow
         9: .line 137
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.executionLatches:Ljava/util/Iterator;
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast java.util.concurrent.CountDownLatch
            invokevirtual java.util.concurrent.CountDownLatch.await:()V
        10: .line 138
            goto 12
      StackMap locals:
      StackMap stack: java.lang.InterruptedException
        11: pop
        12: .line 140
      StackMap locals:
      StackMap stack:
            new java.util.concurrent.atomic.AtomicBoolean
            dup
            iconst_0
            invokespecial java.util.concurrent.atomic.AtomicBoolean.<init>:(Z)V
            astore 1 /* onExecuteCalled */
        start local 1 // java.util.concurrent.atomic.AtomicBoolean onExecuteCalled
        13: .line 141
            new java.util.concurrent.atomic.AtomicBoolean
            dup
            iconst_0
            invokespecial java.util.concurrent.atomic.AtomicBoolean.<init>:(Z)V
            astore 2 /* createEventNodeCalled */
        start local 2 // java.util.concurrent.atomic.AtomicBoolean createEventNodeCalled
        14: .line 142
            new java.util.concurrent.CountDownLatch
            dup
            iconst_1
            invokespecial java.util.concurrent.CountDownLatch.<init>:(I)V
            astore 3 /* executionEventLatch */
        start local 3 // java.util.concurrent.CountDownLatch executionEventLatch
        15: .line 144
            aload 0 /* this */
            getfield com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread.env:Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;
            invokevirtual com.oracle.truffle.api.instrumentation.TruffleInstrument$Env.getInstrumenter:()Lcom/oracle/truffle/api/instrumentation/Instrumenter;
            getstatic com.oracle.truffle.api.instrumentation.SourceFilter.ANY:Lcom/oracle/truffle/api/instrumentation/SourceFilter;
            new com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread$1
            dup
            aload 0 /* this */
            aload 2 /* createEventNodeCalled */
            aload 3 /* executionEventLatch */
            aload 1 /* onExecuteCalled */
            invokespecial com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread$1.<init>:(Lcom/oracle/truffle/api/instrumentation/test/GR25718Test$InstrumentationThread;Ljava/util/concurrent/atomic/AtomicBoolean;Ljava/util/concurrent/CountDownLatch;Ljava/util/concurrent/atomic/AtomicBoolean;)V
        16: .line 169
            iconst_1
        17: .line 144
            invokevirtual com.oracle.truffle.api.instrumentation.Instrumenter.attachExecuteSourceListener:(Lcom/oracle/truffle/api/instrumentation/SourceFilter;Lcom/oracle/truffle/api/instrumentation/ExecuteSourceListener;Z)Lcom/oracle/truffle/api/instrumentation/EventBinding;
            pop
        18: .line 170
            return
        end local 3 // java.util.concurrent.CountDownLatch executionEventLatch
        end local 2 // java.util.concurrent.atomic.AtomicBoolean createEventNodeCalled
        end local 1 // java.util.concurrent.atomic.AtomicBoolean onExecuteCalled
        end local 0 // com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread this
      LocalVariableTable:
        Start  End  Slot                   Name  Signature
            0   19     0                   this  Lcom/oracle/truffle/api/instrumentation/test/GR25718Test$InstrumentationThread;
            2    5     3                      c  Lorg/graalvm/polyglot/Context;
           13   19     1        onExecuteCalled  Ljava/util/concurrent/atomic/AtomicBoolean;
           14   19     2  createEventNodeCalled  Ljava/util/concurrent/atomic/AtomicBoolean;
           15   19     3    executionEventLatch  Ljava/util/concurrent/CountDownLatch;
      Exception table:
        from    to  target  type
           2     3       4  any
           1     6       6  any
           9    10      11  Class java.lang.InterruptedException
}
SourceFile: "GR25718Test.java"
NestHost: com.oracle.truffle.api.instrumentation.test.GR25718Test
InnerClasses:
  public final Env = com.oracle.truffle.api.instrumentation.TruffleInstrument$Env of com.oracle.truffle.api.instrumentation.TruffleInstrument
  private InstrumentationThread = com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread of com.oracle.truffle.api.instrumentation.test.GR25718Test
  com.oracle.truffle.api.instrumentation.test.GR25718Test$InstrumentationThread$1
  public final Builder = org.graalvm.polyglot.Context$Builder of org.graalvm.polyglot.Context