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.MultimapBuilder$EnumSetSupplier<V extends java.lang.Enum<V>> implements com.google.common.base.Supplier<java.util.Set<V>>, java.io.Serializable
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.google.common.collect.MultimapBuilder$EnumSetSupplier
  super_class: java.lang.Object
{
  private final java.lang.Class<V> clazz;
    descriptor: Ljava/lang/Class;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/lang/Class<TV;>;

  void <init>(java.lang.Class<V>);
    descriptor: (Ljava/lang/Class;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.collect.MultimapBuilder$EnumSetSupplier this
        start local 1 // java.lang.Class clazz
         0: .line 257
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 258
            aload 0 /* this */
            aload 1 /* clazz */
            invokestatic com.google.common.base.Preconditions.checkNotNull:(Ljava/lang/Object;)Ljava/lang/Object;
            checkcast java.lang.Class
            putfield com.google.common.collect.MultimapBuilder$EnumSetSupplier.clazz:Ljava/lang/Class;
         2: .line 259
            return
        end local 1 // java.lang.Class clazz
        end local 0 // com.google.common.collect.MultimapBuilder$EnumSetSupplier this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    3     0   this  Lcom/google/common/collect/MultimapBuilder$EnumSetSupplier<TV;>;
            0    3     1  clazz  Ljava/lang/Class<TV;>;
    Signature: (Ljava/lang/Class<TV;>;)V
    MethodParameters:
       Name  Flags
      clazz  

  public java.util.Set<V> get();
    descriptor: ()Ljava/util/Set;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.collect.MultimapBuilder$EnumSetSupplier this
         0: .line 263
            aload 0 /* this */
            getfield com.google.common.collect.MultimapBuilder$EnumSetSupplier.clazz:Ljava/lang/Class;
            invokestatic java.util.EnumSet.noneOf:(Ljava/lang/Class;)Ljava/util/EnumSet;
            areturn
        end local 0 // com.google.common.collect.MultimapBuilder$EnumSetSupplier this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/collect/MultimapBuilder$EnumSetSupplier<TV;>;
    Signature: ()Ljava/util/Set<TV;>;

  public java.lang.Object get();
    descriptor: ()Ljava/lang/Object;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=1, locals=1, args_size=1
         0: .line 1
            aload 0
            invokevirtual com.google.common.collect.MultimapBuilder$EnumSetSupplier.get:()Ljava/util/Set;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
Signature: <V:Ljava/lang/Enum<TV;>;>Ljava/lang/Object;Lcom/google/common/base/Supplier<Ljava/util/Set<TV;>;>;Ljava/io/Serializable;
SourceFile: "MultimapBuilder.java"
NestHost: com.google.common.collect.MultimapBuilder
InnerClasses:
  private final EnumSetSupplier = com.google.common.collect.MultimapBuilder$EnumSetSupplier of com.google.common.collect.MultimapBuilder