Class ForwardingDeque<E>

  extended by
      extended by<E>
          extended by<E>
              extended by<E>
All Implemented Interfaces:
Iterable<E>, Collection<E>, Deque<E>, Queue<E>

public abstract class ForwardingDeque<E>
extends ForwardingQueue<E>
implements Deque<E>

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

Warning: The methods of ForwardingDeque forward indiscriminately to the methods of the delegate. For example, overriding ForwardingCollection.add(E) alone will not change the behavior of ForwardingQueue.offer(E) which can lead to unexpected behavior. In this case, you should override offer as well, either providing your own implementation, or delegating to the provided standardOffer method.

The standard methods are not guaranteed to be thread-safe, even when all of the methods that they depend on are thread-safe.

Kurt Alfred Kluever

Constructor Summary
protected ForwardingDeque()
          Constructor for use by subclasses.
Method Summary
 void addFirst(E e)
 void addLast(E e)
protected abstract  Deque<E> delegate()
          Returns the backing delegate instance that methods are forwarded to.
 Iterator<E> descendingIterator()
 E getFirst()
 E getLast()
 boolean offerFirst(E e)
 boolean offerLast(E e)
 E peekFirst()
 E peekLast()
 E pollFirst()
 E pollLast()
 E pop()
 void push(E e)
 E removeFirst()
 boolean removeFirstOccurrence(Object o)
 E removeLast()
 boolean removeLastOccurrence(Object o)
Methods inherited from class
element, offer, peek, poll, remove, standardOffer, standardPeek, standardPoll
Methods inherited from class
add, addAll, clear, contains, containsAll, isEmpty, iterator, remove, removeAll, retainAll, size, standardAddAll, standardClear, standardContains, standardContainsAll, standardIsEmpty, standardRemove, standardRemoveAll, standardRetainAll, standardToArray, standardToArray, standardToString, toArray, toArray
Methods inherited from class
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Methods inherited from interface java.util.Deque
add, contains, element, iterator, offer, peek, poll, remove, remove, size
Methods inherited from interface java.util.Collection
addAll, clear, containsAll, equals, hashCode, isEmpty, removeAll, retainAll, toArray, toArray

Constructor Detail


protected ForwardingDeque()
Constructor for use by subclasses.

Method Detail


protected abstract Deque<E> 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 ForwardingQueue<E>


public void addFirst(E e)
Specified by:
addFirst in interface Deque<E>


public void addLast(E e)
Specified by:
addLast in interface Deque<E>


public Iterator<E> descendingIterator()
Specified by:
descendingIterator in interface Deque<E>


public E getFirst()
Specified by:
getFirst in interface Deque<E>


public E getLast()
Specified by:
getLast in interface Deque<E>


public boolean offerFirst(E e)
Specified by:
offerFirst in interface Deque<E>


public boolean offerLast(E e)
Specified by:
offerLast in interface Deque<E>


public E peekFirst()
Specified by:
peekFirst in interface Deque<E>


public E peekLast()
Specified by:
peekLast in interface Deque<E>


public E pollFirst()
Specified by:
pollFirst in interface Deque<E>


public E pollLast()
Specified by:
pollLast in interface Deque<E>


public E pop()
Specified by:
pop in interface Deque<E>


public void push(E e)
Specified by:
push in interface Deque<E>


public E removeFirst()
Specified by:
removeFirst in interface Deque<E>


public E removeLast()
Specified by:
removeLast in interface Deque<E>


public boolean removeFirstOccurrence(Object o)
Specified by:
removeFirstOccurrence in interface Deque<E>


public boolean removeLastOccurrence(Object o)
Specified by:
removeLastOccurrence in interface Deque<E>

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