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$12 extends com.google.common.collect.AbstractMapEntry<K, V2>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.collect.Maps$12
  super_class: com.google.common.collect.AbstractMapEntry
{
  private final java.util.Map$Entry val$entry;
    descriptor: Ljava/util/Map$Entry;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final com.google.common.collect.Maps$EntryTransformer val$transformer;
    descriptor: Lcom/google/common/collect/Maps$EntryTransformer;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(java.util.Map$Entry, com.google.common.collect.Maps$EntryTransformer);
    descriptor: (Ljava/util/Map$Entry;Lcom/google/common/collect/Maps$EntryTransformer;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.google.common.collect.Maps$12 this
         0: .line 1983
            aload 0 /* this */
            aload 1
            putfield com.google.common.collect.Maps$12.val$entry:Ljava/util/Map$Entry;
            aload 0 /* this */
            aload 2
            putfield com.google.common.collect.Maps$12.val$transformer:Lcom/google/common/collect/Maps$EntryTransformer;
            aload 0 /* this */
            invokespecial com.google.common.collect.AbstractMapEntry.<init>:()V
            return
        end local 0 // com.google.common.collect.Maps$12 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$12;
    MethodParameters:
                 Name  Flags
      val$entry        final
      val$transformer  final

  public K getKey();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.Maps$12 this
         0: .line 1986
            aload 0 /* this */
            getfield com.google.common.collect.Maps$12.val$entry:Ljava/util/Map$Entry;
            invokeinterface java.util.Map$Entry.getKey:()Ljava/lang/Object;
            areturn
        end local 0 // com.google.common.collect.Maps$12 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$12;
    Signature: ()TK;

  public V2 getValue();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // com.google.common.collect.Maps$12 this
         0: .line 1991
            aload 0 /* this */
            getfield com.google.common.collect.Maps$12.val$transformer:Lcom/google/common/collect/Maps$EntryTransformer;
            aload 0 /* this */
            getfield com.google.common.collect.Maps$12.val$entry:Ljava/util/Map$Entry;
            invokeinterface java.util.Map$Entry.getKey:()Ljava/lang/Object;
            aload 0 /* this */
            getfield com.google.common.collect.Maps$12.val$entry:Ljava/util/Map$Entry;
            invokeinterface java.util.Map$Entry.getValue:()Ljava/lang/Object;
            invokeinterface com.google.common.collect.Maps$EntryTransformer.transformEntry:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
            areturn
        end local 0 // com.google.common.collect.Maps$12 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/Maps$12;
    Signature: ()TV2;
}
Signature: Lcom/google/common/collect/AbstractMapEntry<TK;TV2;>;
SourceFile: "Maps.java"
EnclosingMethod: com.google.common.collect.Maps.transformEntry:(Lcom/google/common/collect/Maps$EntryTransformer;Ljava/util/Map$Entry;)Ljava/util/Map$Entry;
NestHost: com.google.common.collect.Maps
InnerClasses:
  com.google.common.collect.Maps$12
  public abstract EntryTransformer = com.google.common.collect.Maps$EntryTransformer of com.google.common.collect.Maps
  public abstract Entry = java.util.Map$Entry of java.util.Map