com.google.common.collect
Class ForwardingIterator<T>

java.lang.Object
  extended by com.google.common.collect.ForwardingObject
      extended by com.google.common.collect.ForwardingIterator<T>
All Implemented Interfaces:
Iterator<T>
Direct Known Subclasses:
ForwardingListIterator

public abstract class ForwardingIterator<T>
extends ForwardingObject
implements Iterator<T>

An iterator which forwards all its method calls to another iterator. Subclasses should override one or more methods to modify the behavior of the backing iterator as desired per the decorator pattern.

Since:
2 (imported from Google Collections Library)
Author:
Kevin Bourrillion

Constructor Summary
protected ForwardingIterator()
          Constructor for use by subclasses.
 
Method Summary
protected abstract  Iterator<T> delegate()
          Returns the backing delegate instance that methods are forwarded to.
 boolean hasNext()
          Returns true if the iteration has more elements.
 T next()
          Returns the next element in the iteration.
 void remove()
          Removes from the underlying collection the last element returned by this iterator (optional operation).
 
Methods inherited from class com.google.common.collect.ForwardingObject
toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ForwardingIterator

protected ForwardingIterator()
Constructor for use by subclasses.

Method Detail

delegate

protected abstract Iterator<T> delegate()
Description copied from class: ForwardingObject
Returns the backing delegate instance that methods are forwarded to. Abstract subclasses generally override this method with an abstract method that has a more specific return type, such as ForwardingSet.delegate(). Concrete subclasses override this method to supply the instance being decorated.

Specified by:
delegate in class ForwardingObject

hasNext

public boolean hasNext()
Description copied from interface: java.util.Iterator
Returns true if the iteration has more elements. (In other words, returns true if Iterator.next() would return an element rather than throwing an exception.)

Specified by:
hasNext in interface Iterator<T>
Returns:
true if the iteration has more elements

next

public T next()
Description copied from interface: java.util.Iterator
Returns the next element in the iteration.

Specified by:
next in interface Iterator<T>
Returns:
the next element in the iteration

remove

public void remove()
Description copied from interface: java.util.Iterator
Removes from the underlying collection the last element returned by this iterator (optional operation). This method can be called only once per call to Iterator.next(). The behavior of an iterator is unspecified if the underlying collection is modified while the iteration is in progress in any way other than by calling this method.

Specified by:
remove in interface Iterator<T>