https://github.com/google/guava/guava: Guava is a suite of core and expanded libraries that include utility classes, google's collections, io classes, and much much more. 
class com.google.common.collect.Maps$AsMapView$1EntrySetImpl extends com.google.common.collect.Maps$EntrySet<K, V>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.collect.Maps$AsMapView$1EntrySetImpl
  super_class: com.google.common.collect.Maps$EntrySet
{
  final com.google.common.collect.Maps$AsMapView this$1;
    descriptor: Lcom/google/common/collect/Maps$AsMapView;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.google.common.collect.Maps$AsMapView);
    descriptor: (Lcom/google/common/collect/Maps$AsMapView;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
         0: .line 936
            aload 0 /* this */
            aload 1
            putfield com.google.common.collect.Maps$AsMapView$1EntrySetImpl.this$1:Lcom/google/common/collect/Maps$AsMapView;
            aload 0 /* this */
            invokespecial com.google.common.collect.Maps$EntrySet.<init>:()V
            return
        end local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$AsMapView$1EntrySetImpl;
    MethodParameters:
        Name  Flags
      this$0  final

  java.util.Map<K, V> map();
    descriptor: ()Ljava/util/Map;
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
         0: .line 939
            aload 0 /* this */
            getfield com.google.common.collect.Maps$AsMapView$1EntrySetImpl.this$1:Lcom/google/common/collect/Maps$AsMapView;
            areturn
        end local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$AsMapView$1EntrySetImpl;
    Signature: ()Ljava/util/Map<TK;TV;>;

  public java.util.Iterator<java.util.Map$Entry<K, V>> iterator();
    descriptor: ()Ljava/util/Iterator;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
         0: .line 944
            aload 0 /* this */
            getfield com.google.common.collect.Maps$AsMapView$1EntrySetImpl.this$1:Lcom/google/common/collect/Maps$AsMapView;
            invokevirtual com.google.common.collect.Maps$AsMapView.backingSet:()Ljava/util/Set;
            aload 0 /* this */
            getfield com.google.common.collect.Maps$AsMapView$1EntrySetImpl.this$1:Lcom/google/common/collect/Maps$AsMapView;
            getfield com.google.common.collect.Maps$AsMapView.function:Lcom/google/common/base/Function;
            invokestatic com.google.common.collect.Maps.asMapEntryIterator:(Ljava/util/Set;Lcom/google/common/base/Function;)Ljava/util/Iterator;
            areturn
        end local 0 // com.google.common.collect.Maps$AsMapView$1EntrySetImpl this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$AsMapView$1EntrySetImpl;
    Signature: ()Ljava/util/Iterator<Ljava/util/Map$Entry<TK;TV;>;>;
}
Signature: Lcom/google/common/collect/Maps$EntrySet<TK;TV;>;
SourceFile: "Maps.java"
EnclosingMethod: com.google.common.collect.Maps$AsMapView.createEntrySet:()Ljava/util/Set;
NestHost: com.google.common.collect.Maps
InnerClasses:
  private AsMapView = com.google.common.collect.Maps$AsMapView of com.google.common.collect.Maps
  EntrySetImpl = com.google.common.collect.Maps$AsMapView$1EntrySetImpl
  abstract EntrySet = com.google.common.collect.Maps$EntrySet of com.google.common.collect.Maps
  public abstract Entry = java.util.Map$Entry of java.util.Map