# Package org.apache.commons.collections4.iterators

This package contains implementations of the `Iterator` interface.

See: Description

- Class Summary
  Class | Description
  --- | ---
  AbstractEmptyMapIterator<K,V> | Provides an implementation of an empty map iterator.
  AbstractIteratorDecorator<E> | Provides basic behaviour for decorating an iterator with extra functionality.
  AbstractListIteratorDecorator<E> | Provides basic behaviour for decorating a list iterator with extra functionality.
  AbstractMapIteratorDecorator<K,V> | Provides basic behaviour for decorating a map iterator with extra functionality.
  AbstractOrderedMapIteratorDecorator<K,V> | Provides basic behaviour for decorating an ordered map iterator with extra functionality.
  AbstractUntypedIteratorDecorator<I,O> | Provides basic behaviour for decorating an iterator with extra functionality without committing the generic type of the Iterator implementation.
  ArrayIterator<E> | Implements an `Iterator` over any array.
  ArrayListIterator<E> | Implements a `ListIterator` over an array.
  BoundedIterator<E> | Decorates another iterator to return elements in a specific range.
  CollatingIterator<E> | Provides an ordered iteration over the elements contained in a collection of ordered Iterators.
  EmptyIterator<E> | Provides an implementation of an empty iterator.
  EmptyListIterator<E> | Provides an implementation of an empty list iterator.
  EmptyMapIterator<K,V> | Provides an implementation of an empty map iterator.
  EmptyOrderedIterator<E> | Provides an implementation of an empty ordered iterator.
  EmptyOrderedMapIterator<K,V> | Provides an implementation of an empty ordered map iterator.
  EntrySetMapIterator<K,V> | Implements a `MapIterator` using a Map entrySet.
  EnumerationIterator<E> | Adapter to make `Enumeration` instances appear to be `Iterator` instances.
  FilterIterator<E> | Decorates another `Iterator` using a predicate to filter elements.
  FilterListIterator<E> | Decorates another `ListIterator` using a predicate to filter elements.
  IteratorChain<E> | An IteratorChain is an Iterator that wraps a number of Iterators.
  IteratorEnumeration<E> | Adapter to make an `Iterator` instance appear to be an `Enumeration` instance.
  IteratorIterable<E> | Adapter to make an `Iterator` instance appear to be an `Iterable` instance.
  LazyIteratorChain<E> | An LazyIteratorChain is an Iterator that wraps a number of Iterators in a lazy manner.
  ListIteratorWrapper<E> | Converts an `Iterator` into a `ResettableListIterator`.
  LoopingIterator<E> | An Iterator that restarts when it reaches the end.
  LoopingListIterator<E> | A ListIterator that restarts when it reaches the end or when it reaches the beginning.
  NodeListIterator | An `Iterator` over a `NodeList`.
  ObjectArrayIterator<E> | An `Iterator` over an array of objects.
  ObjectArrayListIterator<E> | Implements a `ListIterator` over an array of objects.
  ObjectGraphIterator<E> | An Iterator that can traverse multiple iterators down an object graph.
  PeekingIterator<E> | Decorates an iterator to support one-element lookahead while iterating.
  PermutationIterator<E> | This iterator creates permutations of an input collection, using the Steinhaus-Johnson-Trotter algorithm (also called plain changes).
  PushbackIterator<E> | Decorates an iterator to support pushback of elements.
  ReverseListIterator<E> | Iterates backwards through a List, starting with the last element and continuing to the first.
  SingletonIterator<E> | `SingletonIterator` is an `Iterator` over a single object instance.
  SingletonListIterator<E> | `SingletonIterator` is an `ListIterator` over a single object instance.
  SkippingIterator<E> | Decorates another iterator to skip the first N elements.
  TransformIterator<I,O> | Decorates an iterator such that each element returned is transformed.
  UniqueFilterIterator<E> | A FilterIterator which only returns "unique" Objects.
  UnmodifiableIterator<E> | Decorates an iterator such that it cannot be modified.
  UnmodifiableListIterator<E> | Decorates a list iterator such that it cannot be modified.
  UnmodifiableMapIterator<K,V> | Decorates a map iterator such that it cannot be modified.
  UnmodifiableOrderedMapIterator<K,V> | Decorates an ordered map iterator such that it cannot be modified.
  ZippingIterator<E> | Provides an interleaved iteration over the elements contained in a collection of Iterators.

## Package org.apache.commons.collections4.iterators Description

This package contains implementations of the `Iterator` interface.

You may also consider using `IteratorUtils`, which is a single class that uses static methods to construct instances of the classes in this package.

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