https://www.graalvm.org/ 
class com.oracle.truffle.polyglot.HostClassDesc$Members$1 implements java.util.function.BiFunction<com.oracle.truffle.polyglot.HostMethodDesc, com.oracle.truffle.polyglot.HostMethodDesc, com.oracle.truffle.polyglot.HostMethodDesc>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.polyglot.HostClassDesc$Members$1
  super_class: java.lang.Object
{
  void <init>();
    descriptor: ()V
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.polyglot.HostClassDesc$Members$1 this
         0: .line 126
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.truffle.polyglot.HostClassDesc$Members$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/polyglot/HostClassDesc$Members$1;

  public com.oracle.truffle.polyglot.HostMethodDesc apply(com.oracle.truffle.polyglot.HostMethodDesc, com.oracle.truffle.polyglot.HostMethodDesc);
    descriptor: (Lcom/oracle/truffle/polyglot/HostMethodDesc;Lcom/oracle/truffle/polyglot/HostMethodDesc;)Lcom/oracle/truffle/polyglot/HostMethodDesc;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.oracle.truffle.polyglot.HostClassDesc$Members$1 this
        start local 1 // com.oracle.truffle.polyglot.HostMethodDesc m1
        start local 2 // com.oracle.truffle.polyglot.HostMethodDesc m2
         0: .line 129
            aload 1 /* m1 */
            aload 2 /* m2 */
            invokestatic com.oracle.truffle.polyglot.HostClassDesc$Members.merge:(Lcom/oracle/truffle/polyglot/HostMethodDesc;Lcom/oracle/truffle/polyglot/HostMethodDesc;)Lcom/oracle/truffle/polyglot/HostMethodDesc;
            areturn
        end local 2 // com.oracle.truffle.polyglot.HostMethodDesc m2
        end local 1 // com.oracle.truffle.polyglot.HostMethodDesc m1
        end local 0 // com.oracle.truffle.polyglot.HostClassDesc$Members$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/polyglot/HostClassDesc$Members$1;
            0    1     1    m1  Lcom/oracle/truffle/polyglot/HostMethodDesc;
            0    1     2    m2  Lcom/oracle/truffle/polyglot/HostMethodDesc;
    MethodParameters:
      Name  Flags
      m1    
      m2    

  public java.lang.Object apply(java.lang.Object, java.lang.Object);
    descriptor: (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=3, locals=3, args_size=3
         0: .line 1
            aload 0
            aload 1
            checkcast com.oracle.truffle.polyglot.HostMethodDesc
            aload 2
            checkcast com.oracle.truffle.polyglot.HostMethodDesc
            invokevirtual com.oracle.truffle.polyglot.HostClassDesc$Members$1.apply:(Lcom/oracle/truffle/polyglot/HostMethodDesc;Lcom/oracle/truffle/polyglot/HostMethodDesc;)Lcom/oracle/truffle/polyglot/HostMethodDesc;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Ljava/lang/Object;Ljava/util/function/BiFunction<Lcom/oracle/truffle/polyglot/HostMethodDesc;Lcom/oracle/truffle/polyglot/HostMethodDesc;Lcom/oracle/truffle/polyglot/HostMethodDesc;>;
SourceFile: "HostClassDesc.java"
EnclosingMethod: com.oracle.truffle.polyglot.HostClassDesc$Members
NestHost: com.oracle.truffle.polyglot.HostClassDesc
InnerClasses:
  private Members = com.oracle.truffle.polyglot.HostClassDesc$Members of com.oracle.truffle.polyglot.HostClassDesc
  com.oracle.truffle.polyglot.HostClassDesc$Members$1