https://openjdk.java.net/ 
public interface com.sun.jdi.event.MonitorContendedEnteredEvent extends com.sun.jdi.event.LocatableEvent
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: com.sun.jdi.event.MonitorContendedEnteredEvent
  super_class: java.lang.Object
{
  public abstract com.sun.jdi.ThreadReference thread();
    descriptor: ()Lcom/sun/jdi/ThreadReference;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract com.sun.jdi.ObjectReference monitor();
    descriptor: ()Lcom/sun/jdi/ObjectReference;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
}
SourceFile: "MonitorContendedEnteredEvent.java"