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.AbstractMapBasedMultimap$1 extends com.google.common.collect.AbstractMapBasedMultimap<K, V>.Itr<V>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.collect.AbstractMapBasedMultimap$1
  super_class: com.google.common.collect.AbstractMapBasedMultimap$Itr
{
  final com.google.common.collect.AbstractMapBasedMultimap this$0;
    descriptor: Lcom/google/common/collect/AbstractMapBasedMultimap;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.google.common.collect.AbstractMapBasedMultimap, com.google.common.collect.AbstractMapBasedMultimap);
    descriptor: (Lcom/google/common/collect/AbstractMapBasedMultimap;Lcom/google/common/collect/AbstractMapBasedMultimap;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.google.common.collect.AbstractMapBasedMultimap$1 this
         0: .line 1184
            aload 0 /* this */
            aload 2
            putfield com.google.common.collect.AbstractMapBasedMultimap$1.this$0:Lcom/google/common/collect/AbstractMapBasedMultimap;
            aload 0 /* this */
            aload 1
            invokespecial com.google.common.collect.AbstractMapBasedMultimap$Itr.<init>:(Lcom/google/common/collect/AbstractMapBasedMultimap;)V
            return
        end local 0 // com.google.common.collect.AbstractMapBasedMultimap$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/AbstractMapBasedMultimap$1;
    MethodParameters:
        Name  Flags
      this$0  final
      this$1  final

  V output(K, );
    descriptor: (Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0000) 
    Code:
      stack=1, locals=3, args_size=3
        start local 0 // com.google.common.collect.AbstractMapBasedMultimap$1 this
        start local 1 // java.lang.Object key
        start local 2 // java.lang.Object value
         0: .line 1187
            aload 2 /* value */
            areturn
        end local 2 // java.lang.Object value
        end local 1 // java.lang.Object key
        end local 0 // com.google.common.collect.AbstractMapBasedMultimap$1 this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0   this  Lcom/google/common/collect/AbstractMapBasedMultimap$1;
            0    1     1    key  TK;
            0    1     2  value  TV;
    Signature: (TK;TV;)TV;
    MethodParameters:
       Name  Flags
      key    
      value  
}
Signature: Lcom/google/common/collect/AbstractMapBasedMultimap<TK;TV;>.Itr<TV;>;
SourceFile: "AbstractMapBasedMultimap.java"
EnclosingMethod: com.google.common.collect.AbstractMapBasedMultimap.valueIterator:()Ljava/util/Iterator;
NestHost: com.google.common.collect.AbstractMapBasedMultimap
InnerClasses:
  com.google.common.collect.AbstractMapBasedMultimap$1
  private abstract Itr = com.google.common.collect.AbstractMapBasedMultimap$Itr of com.google.common.collect.AbstractMapBasedMultimap