net.datastructures

Interface Queue<E>

All Known Implementing Classes:

NodeQueue

public interface Queue<E>

Interface for a queue: a collection of elements that are inserted and removed according to the first-in first-out principle.

See Also:

EmptyQueueException

Method Summary

Modifier and Type	Method and Description
E	dequeue() Removes the element at the front of the queue.
void	enqueue(E element) Inserts an element at the rear of the queue.
E	front() Inspects the element at the front of the queue.
boolean	isEmpty() Returns whether the queue is empty.
int	size() Returns the number of elements in the queue.

Method Detail

dequeue

E dequeue()
   throws EmptyQueueException

Removes the element at the front of the queue.

Returns:

element removed.

Throws:

EmptyQueueException - if the queue is empty.

enqueue

void enqueue(E element)

Inserts an element at the rear of the queue.

Parameters:

element - new element to be inserted.

front

E front()
 throws EmptyQueueException

Inspects the element at the front of the queue.

Returns:

element at the front of the queue.

Throws:

EmptyQueueException - if the queue is empty.

isEmpty

boolean isEmpty()

Returns whether the queue is empty.

Returns:

true if the queue is empty, false otherwise.

size

int size()

Returns the number of elements in the queue.

Returns:

number of elements in the queue.