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. 
final class com.google.common.collect.ImmutableMultiset$ElementSet<E> extends com.google.common.collect.ImmutableSet$Indexed<E>
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.google.common.collect.ImmutableMultiset$ElementSet
  super_class: com.google.common.collect.ImmutableSet$Indexed
{
  private final java.util.List<com.google.common.collect.Multiset$Entry<E>> entries;
    descriptor: Ljava/util/List;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/List<Lcom/google/common/collect/Multiset$Entry<TE;>;>;

  private final com.google.common.collect.Multiset<E> delegate;
    descriptor: Lcom/google/common/collect/Multiset;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lcom/google/common/collect/Multiset<TE;>;

  void <init>(java.util.List<com.google.common.collect.Multiset$Entry<E>>, com.google.common.collect.Multiset<E>);
    descriptor: (Ljava/util/List;Lcom/google/common/collect/Multiset;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
        start local 1 // java.util.List entries
        start local 2 // com.google.common.collect.Multiset delegate
         0: .line 592
            aload 0 /* this */
            invokespecial com.google.common.collect.ImmutableSet$Indexed.<init>:()V
         1: .line 593
            aload 0 /* this */
            aload 1 /* entries */
            putfield com.google.common.collect.ImmutableMultiset$ElementSet.entries:Ljava/util/List;
         2: .line 594
            aload 0 /* this */
            aload 2 /* delegate */
            putfield com.google.common.collect.ImmutableMultiset$ElementSet.delegate:Lcom/google/common/collect/Multiset;
         3: .line 595
            return
        end local 2 // com.google.common.collect.Multiset delegate
        end local 1 // java.util.List entries
        end local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    4     0      this  Lcom/google/common/collect/ImmutableMultiset$ElementSet<TE;>;
            0    4     1   entries  Ljava/util/List<Lcom/google/common/collect/Multiset$Entry<TE;>;>;
            0    4     2  delegate  Lcom/google/common/collect/Multiset<TE;>;
    Signature: (Ljava/util/List<Lcom/google/common/collect/Multiset$Entry<TE;>;>;Lcom/google/common/collect/Multiset<TE;>;)V
    MethodParameters:
          Name  Flags
      entries   
      delegate  

  E get();
    descriptor: (I)Ljava/lang/Object;
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
        start local 1 // int index
         0: .line 599
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableMultiset$ElementSet.entries:Ljava/util/List;
            iload 1 /* index */
            invokeinterface java.util.List.get:(I)Ljava/lang/Object;
            checkcast com.google.common.collect.Multiset$Entry
            invokeinterface com.google.common.collect.Multiset$Entry.getElement:()Ljava/lang/Object;
            areturn
        end local 1 // int index
        end local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0   this  Lcom/google/common/collect/ImmutableMultiset$ElementSet<TE;>;
            0    1     1  index  I
    Signature: (I)TE;
    MethodParameters:
       Name  Flags
      index  

  public boolean contains(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
        start local 1 // java.lang.Object object
         0: .line 604
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableMultiset$ElementSet.delegate:Lcom/google/common/collect/Multiset;
            aload 1 /* object */
            invokeinterface com.google.common.collect.Multiset.contains:(Ljava/lang/Object;)Z
            ireturn
        end local 1 // java.lang.Object object
        end local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    1     0    this  Lcom/google/common/collect/ImmutableMultiset$ElementSet<TE;>;
            0    1     1  object  Ljava/lang/Object;
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
        Name  Flags
      object  

  boolean isPartialView();
    descriptor: ()Z
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
         0: .line 609
            iconst_1
            ireturn
        end local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/ImmutableMultiset$ElementSet<TE;>;

  public int size();
    descriptor: ()I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
         0: .line 614
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableMultiset$ElementSet.entries:Ljava/util/List;
            invokeinterface java.util.List.size:()I
            ireturn
        end local 0 // com.google.common.collect.ImmutableMultiset$ElementSet this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/ImmutableMultiset$ElementSet<TE;>;
}
Signature: <E:Ljava/lang/Object;>Lcom/google/common/collect/ImmutableSet$Indexed<TE;>;
SourceFile: "ImmutableMultiset.java"
NestHost: com.google.common.collect.ImmutableMultiset
InnerClasses:
  final ElementSet = com.google.common.collect.ImmutableMultiset$ElementSet of com.google.common.collect.ImmutableMultiset
  abstract Indexed = com.google.common.collect.ImmutableSet$Indexed of com.google.common.collect.ImmutableSet
  public abstract Entry = com.google.common.collect.Multiset$Entry of com.google.common.collect.Multiset