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$SerializedForm implements java.io.Serializable
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.collect.ImmutableSet$SerializedForm
  super_class: java.lang.Object
{
  final java.lang.Object[] elements;
    descriptor: [Ljava/lang/Object;
    flags: (0x0010) ACC_FINAL

  private static final long serialVersionUID;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 0

  void <init>(java.lang.Object[]);
    descriptor: ([Ljava/lang/Object;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.ImmutableSet$SerializedForm this
        start local 1 // java.lang.Object[] elements
         0: .line 397
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 398
            aload 0 /* this */
            aload 1 /* elements */
            putfield com.google.common.collect.ImmutableSet$SerializedForm.elements:[Ljava/lang/Object;
         2: .line 399
            return
        end local 1 // java.lang.Object[] elements
        end local 0 // com.google.common.collect.ImmutableSet$SerializedForm this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    3     0      this  Lcom/google/common/collect/ImmutableSet$SerializedForm;
            0    3     1  elements  [Ljava/lang/Object;
    MethodParameters:
          Name  Flags
      elements  

  java.lang.Object readResolve();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.ImmutableSet$SerializedForm this
         0: .line 402
            aload 0 /* this */
            getfield com.google.common.collect.ImmutableSet$SerializedForm.elements:[Ljava/lang/Object;
            invokestatic com.google.common.collect.ImmutableSet.copyOf:([Ljava/lang/Object;)Lcom/google/common/collect/ImmutableSet;
            areturn
        end local 0 // com.google.common.collect.ImmutableSet$SerializedForm this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/ImmutableSet$SerializedForm;
}
SourceFile: "ImmutableSet.java"
NestHost: com.google.common.collect.ImmutableSet
InnerClasses:
  private SerializedForm = com.google.common.collect.ImmutableSet$SerializedForm of com.google.common.collect.ImmutableSet