https://www.graalvm.org/ 
class com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1 implements java.util.function.Function<java.lang.Object, java.lang.Object>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1
  super_class: java.lang.Object
{
  final com.oracle.truffle.tck.tests.JavaHostLanguageProvider this$0;
    descriptor: Lcom/oracle/truffle/tck/tests/JavaHostLanguageProvider;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.tck.tests.JavaHostLanguageProvider);
    descriptor: (Lcom/oracle/truffle/tck/tests/JavaHostLanguageProvider;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1 this
         0: .line 182
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1.this$0:Lcom/oracle/truffle/tck/tests/JavaHostLanguageProvider;
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/tck/tests/JavaHostLanguageProvider$1;
    MethodParameters:
        Name  Flags
      this$0  final

  public java.lang.Object apply(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1 this
        start local 1 // java.lang.Object t
         0: .line 185
            aload 1 /* t */
            areturn
        end local 1 // java.lang.Object t
        end local 0 // com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/tck/tests/JavaHostLanguageProvider$1;
            0    1     1     t  Ljava/lang/Object;
    MethodParameters:
      Name  Flags
      t     
}
Signature: Ljava/lang/Object;Ljava/util/function/Function<Ljava/lang/Object;Ljava/lang/Object;>;
SourceFile: "JavaHostLanguageProvider.java"
EnclosingMethod: com.oracle.truffle.tck.tests.JavaHostLanguageProvider.createValueConstructors:(Lorg/graalvm/polyglot/Context;)Ljava/util/Collection;
NestHost: com.oracle.truffle.tck.tests.JavaHostLanguageProvider
InnerClasses:
  com.oracle.truffle.tck.tests.JavaHostLanguageProvider$1