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

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

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

  void <init>(com.google.common.graph.DirectedGraphConnections$1, java.util.Iterator, java.util.Set);
    descriptor: (Lcom/google/common/graph/DirectedGraphConnections$1;Ljava/util/Iterator;Ljava/util/Set;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=4, args_size=4
        start local 0 // com.google.common.graph.DirectedGraphConnections$1$1 this
         0: .line 243
            aload 0 /* this */
            aload 1
            putfield com.google.common.graph.DirectedGraphConnections$1$1.this$1:Lcom/google/common/graph/DirectedGraphConnections$1;
            aload 0 /* this */
            aload 2
            putfield com.google.common.graph.DirectedGraphConnections$1$1.val$nodeConnections:Ljava/util/Iterator;
            aload 0 /* this */
            aload 3
            putfield com.google.common.graph.DirectedGraphConnections$1$1.val$seenNodes:Ljava/util/Set;
            aload 0 /* this */
            invokespecial com.google.common.collect.AbstractIterator.<init>:()V
            return
        end local 0 // com.google.common.graph.DirectedGraphConnections$1$1 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/graph/DirectedGraphConnections$1$1;
    MethodParameters:
                     Name  Flags
      this$0               final
      val$nodeConnections  final
      val$seenNodes        final

  protected N computeNext();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=2, locals=3, args_size=1
        start local 0 // com.google.common.graph.DirectedGraphConnections$1$1 this
         0: .line 246
            goto 5
         1: .line 247
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.google.common.graph.DirectedGraphConnections$1$1.val$nodeConnections:Ljava/util/Iterator;
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast com.google.common.graph.DirectedGraphConnections$NodeConnection
            astore 1 /* nodeConnection */
        start local 1 // com.google.common.graph.DirectedGraphConnections$NodeConnection nodeConnection
         2: .line 248
            aload 0 /* this */
            getfield com.google.common.graph.DirectedGraphConnections$1$1.val$seenNodes:Ljava/util/Set;
            aload 1 /* nodeConnection */
            getfield com.google.common.graph.DirectedGraphConnections$NodeConnection.node:Ljava/lang/Object;
            invokeinterface java.util.Set.add:(Ljava/lang/Object;)Z
            istore 2 /* added */
        start local 2 // boolean added
         3: .line 249
            iload 2 /* added */
            ifeq 5
         4: .line 250
            aload 1 /* nodeConnection */
            getfield com.google.common.graph.DirectedGraphConnections$NodeConnection.node:Ljava/lang/Object;
            areturn
        end local 2 // boolean added
        end local 1 // com.google.common.graph.DirectedGraphConnections$NodeConnection nodeConnection
         5: .line 246
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.google.common.graph.DirectedGraphConnections$1$1.val$nodeConnections:Ljava/util/Iterator;
            invokeinterface java.util.Iterator.hasNext:()Z
            ifne 1
         6: .line 253
            aload 0 /* this */
            invokevirtual com.google.common.graph.DirectedGraphConnections$1$1.endOfData:()Ljava/lang/Object;
            areturn
        end local 0 // com.google.common.graph.DirectedGraphConnections$1$1 this
      LocalVariableTable:
        Start  End  Slot            Name  Signature
            0    7     0            this  Lcom/google/common/graph/DirectedGraphConnections$1$1;
            2    5     1  nodeConnection  Lcom/google/common/graph/DirectedGraphConnections$NodeConnection<TN;>;
            3    5     2           added  Z
    Signature: ()TN;
}
Signature: Lcom/google/common/collect/AbstractIterator<TN;>;
SourceFile: "DirectedGraphConnections.java"
EnclosingMethod: com.google.common.graph.DirectedGraphConnections$1.iterator:()Lcom/google/common/collect/UnmodifiableIterator;
NestHost: com.google.common.graph.DirectedGraphConnections
InnerClasses:
  com.google.common.graph.DirectedGraphConnections$1
  com.google.common.graph.DirectedGraphConnections$1$1
  private abstract NodeConnection = com.google.common.graph.DirectedGraphConnections$NodeConnection of com.google.common.graph.DirectedGraphConnections