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.Sets$5$1$1$1 extends com.google.common.collect.AbstractIterator<E>
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.collect.Sets$5$1$1$1
  super_class: com.google.common.collect.AbstractIterator
{
  int i;
    descriptor: I
    flags: (0x0000) 

  final com.google.common.collect.Sets$5$1$1 this$3;
    descriptor: Lcom/google/common/collect/Sets$5$1$1;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  private final java.util.BitSet val$copy;
    descriptor: Ljava/util/BitSet;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final com.google.common.collect.ImmutableMap val$index;
    descriptor: Lcom/google/common/collect/ImmutableMap;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(com.google.common.collect.Sets$5$1$1, java.util.BitSet, com.google.common.collect.ImmutableMap);
    descriptor: (Lcom/google/common/collect/Sets$5$1$1;Ljava/util/BitSet;Lcom/google/common/collect/ImmutableMap;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=4, args_size=4
        start local 0 // com.google.common.collect.Sets$5$1$1$1 this
         0: .line 1708
            aload 0 /* this */
            aload 1
            putfield com.google.common.collect.Sets$5$1$1$1.this$3:Lcom/google/common/collect/Sets$5$1$1;
            aload 0 /* this */
            aload 2
            putfield com.google.common.collect.Sets$5$1$1$1.val$copy:Ljava/util/BitSet;
            aload 0 /* this */
            aload 3
            putfield com.google.common.collect.Sets$5$1$1$1.val$index:Lcom/google/common/collect/ImmutableMap;
            aload 0 /* this */
            invokespecial com.google.common.collect.AbstractIterator.<init>:()V
         1: .line 1709
            aload 0 /* this */
            iconst_m1
            putfield com.google.common.collect.Sets$5$1$1$1.i:I
         2: .line 1708
            return
        end local 0 // com.google.common.collect.Sets$5$1$1$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lcom/google/common/collect/Sets$5$1$1$1;
    MethodParameters:
           Name  Flags
      this$0     final
      val$copy   final
      val$index  final

  protected E computeNext();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=4, locals=1, args_size=1
        start local 0 // com.google.common.collect.Sets$5$1$1$1 this
         0: .line 1713
            aload 0 /* this */
            aload 0 /* this */
            getfield com.google.common.collect.Sets$5$1$1$1.val$copy:Ljava/util/BitSet;
            aload 0 /* this */
            getfield com.google.common.collect.Sets$5$1$1$1.i:I
            iconst_1
            iadd
            invokevirtual java.util.BitSet.nextSetBit:(I)I
            putfield com.google.common.collect.Sets$5$1$1$1.i:I
         1: .line 1714
            aload 0 /* this */
            getfield com.google.common.collect.Sets$5$1$1$1.i:I
            iconst_m1
            if_icmpne 3
         2: .line 1715
            aload 0 /* this */
            invokevirtual com.google.common.collect.Sets$5$1$1$1.endOfData:()Ljava/lang/Object;
            areturn
         3: .line 1717
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.google.common.collect.Sets$5$1$1$1.val$index:Lcom/google/common/collect/ImmutableMap;
            invokevirtual com.google.common.collect.ImmutableMap.keySet:()Lcom/google/common/collect/ImmutableSet;
            invokevirtual com.google.common.collect.ImmutableSet.asList:()Lcom/google/common/collect/ImmutableList;
            aload 0 /* this */
            getfield com.google.common.collect.Sets$5$1$1$1.i:I
            invokevirtual com.google.common.collect.ImmutableList.get:(I)Ljava/lang/Object;
            areturn
        end local 0 // com.google.common.collect.Sets$5$1$1$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    4     0  this  Lcom/google/common/collect/Sets$5$1$1$1;
    Signature: ()TE;
}
Signature: Lcom/google/common/collect/AbstractIterator<TE;>;
SourceFile: "Sets.java"
EnclosingMethod: com.google.common.collect.Sets$5$1$1.iterator:()Ljava/util/Iterator;
NestHost: com.google.common.collect.Sets
InnerClasses:
  com.google.common.collect.Sets$5
  com.google.common.collect.Sets$5$1
  com.google.common.collect.Sets$5$1$1
  com.google.common.collect.Sets$5$1$1$1