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

  void <init>(com.google.common.collect.ImmutableSet$Indexed);
    descriptor: (Lcom/google/common/collect/ImmutableSet$Indexed;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
         0: .line 373
            aload 0 /* this */
            aload 1
            putfield com.google.common.collect.ImmutableSet$Indexed$1.this$1:Lcom/google/common/collect/ImmutableSet$Indexed;
            aload 0 /* this */
            invokespecial com.google.common.collect.ImmutableAsList.<init>:()V
            return
        end local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/ImmutableSet$Indexed$1;
    MethodParameters:
        Name  Flags
      this$0  final

  public E get();
    descriptor: (I)Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
        start local 1 // int index
         0: .line 376
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableSet$Indexed$1.this$1:Lcom/google/common/collect/ImmutableSet$Indexed;
            iload 1 /* index */
            invokevirtual com.google.common.collect.ImmutableSet$Indexed.get:(I)Ljava/lang/Object;
            areturn
        end local 1 // int index
        end local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0   this  Lcom/google/common/collect/ImmutableSet$Indexed$1;
            0    1     1  index  I
    Signature: (I)TE;
    MethodParameters:
       Name  Flags
      index  

  com.google.common.collect.ImmutableSet$Indexed<E> delegateCollection();
    descriptor: ()Lcom/google/common/collect/ImmutableSet$Indexed;
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
         0: .line 381
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableSet$Indexed$1.this$1:Lcom/google/common/collect/ImmutableSet$Indexed;
            areturn
        end local 0 // com.google.common.collect.ImmutableSet$Indexed$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/ImmutableSet$Indexed$1;
    Signature: ()Lcom/google/common/collect/ImmutableSet$Indexed<TE;>;

  com.google.common.collect.ImmutableCollection delegateCollection();
    descriptor: ()Lcom/google/common/collect/ImmutableCollection;
    flags: (0x1040) ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=1, locals=1, args_size=1
         0: .line 1
            aload 0
            invokevirtual com.google.common.collect.ImmutableSet$Indexed$1.delegateCollection:()Lcom/google/common/collect/ImmutableSet$Indexed;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: Lcom/google/common/collect/ImmutableAsList<TE;>;
SourceFile: "ImmutableSet.java"
EnclosingMethod: com.google.common.collect.ImmutableSet$Indexed.createAsList:()Lcom/google/common/collect/ImmutableList;
NestHost: com.google.common.collect.ImmutableSet
InnerClasses:
  abstract Indexed = com.google.common.collect.ImmutableSet$Indexed of com.google.common.collect.ImmutableSet
  com.google.common.collect.ImmutableSet$Indexed$1