https://www.graalvm.org/ 
class com.oracle.truffle.tools.profiler.CPUTracer$2 implements java.util.function.Function<com.oracle.truffle.api.source.SourceSection, com.oracle.truffle.tools.profiler.CPUTracer$Payload>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.tools.profiler.CPUTracer$2
  super_class: java.lang.Object
{
  final com.oracle.truffle.tools.profiler.CPUTracer this$0;
    descriptor: Lcom/oracle/truffle/tools/profiler/CPUTracer;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  private final com.oracle.truffle.api.instrumentation.EventContext val$context;
    descriptor: Lcom/oracle/truffle/api/instrumentation/EventContext;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.tools.profiler.CPUTracer, com.oracle.truffle.api.instrumentation.EventContext);
    descriptor: (Lcom/oracle/truffle/tools/profiler/CPUTracer;Lcom/oracle/truffle/api/instrumentation/EventContext;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.oracle.truffle.tools.profiler.CPUTracer$2 this
         0: .line 161
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.tools.profiler.CPUTracer$2.this$0:Lcom/oracle/truffle/tools/profiler/CPUTracer;
            aload 0 /* this */
            aload 2
            putfield com.oracle.truffle.tools.profiler.CPUTracer$2.val$context:Lcom/oracle/truffle/api/instrumentation/EventContext;
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.truffle.tools.profiler.CPUTracer$2 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/tools/profiler/CPUTracer$2;
    MethodParameters:
             Name  Flags
      this$0       final
      val$context  final

  public com.oracle.truffle.tools.profiler.CPUTracer$Payload apply(com.oracle.truffle.api.source.SourceSection);
    descriptor: (Lcom/oracle/truffle/api/source/SourceSection;)Lcom/oracle/truffle/tools/profiler/CPUTracer$Payload;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=7, locals=2, args_size=2
        start local 0 // com.oracle.truffle.tools.profiler.CPUTracer$2 this
        start local 1 // com.oracle.truffle.api.source.SourceSection section
         0: .line 164
            new com.oracle.truffle.tools.profiler.CPUTracer$Payload
            dup
            new com.oracle.truffle.tools.profiler.StackTraceEntry
            dup
            aload 0 /* this */
            getfield com.oracle.truffle.tools.profiler.CPUTracer$2.this$0:Lcom/oracle/truffle/tools/profiler/CPUTracer;
            getfield com.oracle.truffle.tools.profiler.CPUTracer.env:Lcom/oracle/truffle/api/instrumentation/TruffleInstrument$Env;
            invokevirtual com.oracle.truffle.api.instrumentation.TruffleInstrument$Env.getInstrumenter:()Lcom/oracle/truffle/api/instrumentation/Instrumenter;
            aload 0 /* this */
            getfield com.oracle.truffle.tools.profiler.CPUTracer$2.val$context:Lcom/oracle/truffle/api/instrumentation/EventContext;
            iconst_1
            invokespecial com.oracle.truffle.tools.profiler.StackTraceEntry.<init>:(Lcom/oracle/truffle/api/instrumentation/Instrumenter;Lcom/oracle/truffle/api/instrumentation/EventContext;B)V
            invokespecial com.oracle.truffle.tools.profiler.CPUTracer$Payload.<init>:(Lcom/oracle/truffle/tools/profiler/StackTraceEntry;)V
            areturn
        end local 1 // com.oracle.truffle.api.source.SourceSection section
        end local 0 // com.oracle.truffle.tools.profiler.CPUTracer$2 this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    1     0     this  Lcom/oracle/truffle/tools/profiler/CPUTracer$2;
            0    1     1  section  Lcom/oracle/truffle/api/source/SourceSection;
    MethodParameters:
         Name  Flags
      section  

  public java.lang.Object apply(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=2, locals=2, args_size=2
         0: .line 1
            aload 0
            aload 1
            checkcast com.oracle.truffle.api.source.SourceSection
            invokevirtual com.oracle.truffle.tools.profiler.CPUTracer$2.apply:(Lcom/oracle/truffle/api/source/SourceSection;)Lcom/oracle/truffle/tools/profiler/CPUTracer$Payload;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Ljava/lang/Object;Ljava/util/function/Function<Lcom/oracle/truffle/api/source/SourceSection;Lcom/oracle/truffle/tools/profiler/CPUTracer$Payload;>;
SourceFile: "CPUTracer.java"
EnclosingMethod: com.oracle.truffle.tools.profiler.CPUTracer.getCounter:(Lcom/oracle/truffle/api/instrumentation/EventContext;)Lcom/oracle/truffle/tools/profiler/CPUTracer$Payload;
NestHost: com.oracle.truffle.tools.profiler.CPUTracer
InnerClasses:
  public final Env = com.oracle.truffle.api.instrumentation.TruffleInstrument$Env of com.oracle.truffle.api.instrumentation.TruffleInstrument
  com.oracle.truffle.tools.profiler.CPUTracer$2
  public final Payload = com.oracle.truffle.tools.profiler.CPUTracer$Payload of com.oracle.truffle.tools.profiler.CPUTracer