https://www.graalvm.org/ 
class com.oracle.truffle.object.TriePropertyMap$1 extends java.util.AbstractSet<java.util.Map$Entry<java.lang.Object, com.oracle.truffle.api.object.Property>>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.oracle.truffle.object.TriePropertyMap$1
  super_class: java.util.AbstractSet
{
  final com.oracle.truffle.object.TriePropertyMap this$0;
    descriptor: Lcom/oracle/truffle/object/TriePropertyMap;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.oracle.truffle.object.TriePropertyMap);
    descriptor: (Lcom/oracle/truffle/object/TriePropertyMap;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
         0: .line 371
            aload 0 /* this */
            aload 1
            putfield com.oracle.truffle.object.TriePropertyMap$1.this$0:Lcom/oracle/truffle/object/TriePropertyMap;
            aload 0 /* this */
            invokespecial java.util.AbstractSet.<init>:()V
            return
        end local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/object/TriePropertyMap$1;
    MethodParameters:
        Name  Flags
      this$0  final

  public java.util.Iterator<java.util.Map$Entry<java.lang.Object, com.oracle.truffle.api.object.Property>> iterator();
    descriptor: ()Ljava/util/Iterator;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
         0: .line 374
            aload 0 /* this */
            getfield com.oracle.truffle.object.TriePropertyMap$1.this$0:Lcom/oracle/truffle/object/TriePropertyMap;
            invokevirtual com.oracle.truffle.object.TriePropertyMap.orderedEntryIterator:()Ljava/util/Iterator;
            areturn
        end local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/object/TriePropertyMap$1;
    Signature: ()Ljava/util/Iterator<Ljava/util/Map$Entry<Ljava/lang/Object;Lcom/oracle/truffle/api/object/Property;>;>;

  public int size();
    descriptor: ()I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
         0: .line 379
            aload 0 /* this */
            getfield com.oracle.truffle.object.TriePropertyMap$1.this$0:Lcom/oracle/truffle/object/TriePropertyMap;
            invokevirtual com.oracle.truffle.object.TriePropertyMap.size:()I
            ireturn
        end local 0 // com.oracle.truffle.object.TriePropertyMap$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/object/TriePropertyMap$1;
}
Signature: Ljava/util/AbstractSet<Ljava/util/Map$Entry<Ljava/lang/Object;Lcom/oracle/truffle/api/object/Property;>;>;
SourceFile: "TriePropertyMap.java"
EnclosingMethod: com.oracle.truffle.object.TriePropertyMap.entrySet:()Ljava/util/Set;
NestHost: com.oracle.truffle.object.TriePropertyMap
InnerClasses:
  com.oracle.truffle.object.TriePropertyMap$1
  public abstract Entry = java.util.Map$Entry of java.util.Map