pivot.collections
Interface Queue<T>
- All Superinterfaces:
- Collection<T>, java.lang.Iterable<T>, List<T>, Sequence<T>
- All Known Implementing Classes:
- ArrayQueue, LinkedQueue, SynchronizedQueue
public interface Queue<T>
- extends List<T>
Interface representing a first-in, first-out (FIFO) queue when unsorted, and
a priority queue when sorted.
- Author:
- gbrown
Method Summary |
T |
dequeue()
Removes the item from the head of the queue and returns it. |
void |
enqueue(T item)
Enqueues an item. |
T |
peek()
Returns the item at the head of the queue without removing it from the
queue. |
Methods inherited from interface java.lang.Iterable |
iterator |
enqueue
void enqueue(T item)
- Enqueues an item. If the queue is unsorted, the item is added at the
tail of the queue (index 0). Otherwise, it is inserted at the
appropriate index.
- Parameters:
item
- The item to add to the queue.
dequeue
T dequeue()
- Removes the item from the head of the queue and returns it. Calling this
method should have the same effect as:
remove(getLength() - 1, 1);
peek
T peek()
- Returns the item at the head of the queue without removing it from the
queue. Returns null if the queue contains no items. Will also return null
if the head item in the queue is null. getLength() can be used
to distinguish between these two cases.