https://www.graalvm.org/ 
interface com.oracle.truffle.tck.impl.PolyglotEngineWithJavaScript$Multiplier
  minor version: 0
  major version: 59
  flags: flags: (0x0600) ACC_INTERFACE, ACC_ABSTRACT
  this_class: com.oracle.truffle.tck.impl.PolyglotEngineWithJavaScript$Multiplier
  super_class: java.lang.Object
{
  public abstract int multiply(int, int);
    descriptor: (II)I
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    MethodParameters:
      Name  Flags
      a     
      b     
}
SourceFile: "PolyglotEngineWithJavaScript.java"
NestHost: com.oracle.truffle.tck.impl.PolyglotEngineWithJavaScript
InnerClasses:
  abstract Multiplier = com.oracle.truffle.tck.impl.PolyglotEngineWithJavaScript$Multiplier of com.oracle.truffle.tck.impl.PolyglotEngineWithJavaScript
    RuntimeVisibleAnnotations: 
      java.lang.FunctionalInterface()