http://fastutil.di.unimi.it/: fastutil extends the Java Collections Framework by providing type-specific maps, sets, lists and priority queues with a small memory footprint and fast access and insertion; provides also big (64-bit) arrays, sets and lists, and fast, practical I/O classes for binary and text files.
  • Sebastiano Vigna 
final class it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator extends it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap<K, V>.MapIterator implements it.unimi.dsi.fastutil.objects.ObjectIterator<K>
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator
  super_class: it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$MapIterator
{
  final it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap this$0;
    descriptor: Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap;
    flags: (0x1010) ACC_FINAL, ACC_SYNTHETIC

  public void <init>(it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap);
    descriptor: (Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator this
         0: .line 756
            aload 0 /* this */
            aload 1
            putfield it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator.this$0:Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap;
         1: .line 757
            aload 0 /* this */
            aload 1
            invokespecial it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$MapIterator.<init>:(Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap;)V
         2: .line 758
            return
        end local 0 // it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap$KeyIterator;
    MethodParameters:
        Name  Flags
      this$0  final

  public K next();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator this
         0: .line 761
            aload 0 /* this */
            getfield it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator.this$0:Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap;
            getfield it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap.key:[Ljava/lang/Object;
            aload 0 /* this */
            invokevirtual it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator.nextEntry:()I
            aaload
            areturn
        end local 0 // it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap$KeyIterator;
    Signature: ()TK;
}
Signature: Lit/unimi/dsi/fastutil/objects/Object2ObjectOpenCustomHashMap<TK;TV;>.MapIterator;Lit/unimi/dsi/fastutil/objects/ObjectIterator<TK;>;
SourceFile: "Object2ObjectOpenCustomHashMap.java"
NestHost: it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap
InnerClasses:
  private final KeyIterator = it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$KeyIterator of it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap
  private MapIterator = it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap$MapIterator of it.unimi.dsi.fastutil.objects.Object2ObjectOpenCustomHashMap