net.datastructures

Class NodeQueue<E>

java.lang.Object

net.datastructures.NodeQueue<E>

All Implemented Interfaces:

Queue<E>

public class NodeQueue<E>
extends java.lang.Object
implements Queue<E>

Realization of a queue by means of a singly-linked list of nodes. All operations are performed in constant time.

Constructor Summary

Constructors

Constructor and Description
NodeQueue() Creates an empty queue.

Method Summary

Modifier and Type	Method and Description
E	dequeue() Removes the element at the front of the queue.
void	enqueue(E elem) 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.
static void	main(java.lang.String[] args) Test program that performs a series of operations on on a queue and prints the operation performed, the returned element and the content of the stack after each operation.
int	size() Returns the number of elements in the queue.
static void	status(Queue Q, java.lang.String op, java.lang.Object element) Prints information about an operation and the queue.
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

NodeQueue

public NodeQueue()

Creates an empty queue.

Method Detail

dequeue

public E dequeue()
          throws EmptyQueueException

Description copied from interface: Queue

Removes the element at the front of the queue.

Specified by:

dequeue in interface Queue<E>

Returns:

element removed.

Throws:

EmptyQueueException - if the queue is empty.

enqueue

public void enqueue(E elem)

Description copied from interface: Queue

Inserts an element at the rear of the queue.

Specified by:

enqueue in interface Queue<E>

Parameters:

elem - new element to be inserted.

front

public E front()
        throws EmptyQueueException

Description copied from interface: Queue

Inspects the element at the front of the queue.

Specified by:

front in interface Queue<E>

Returns:

element at the front of the queue.

Throws:

EmptyQueueException - if the queue is empty.

isEmpty

public boolean isEmpty()

Description copied from interface: Queue

Returns whether the queue is empty.

Specified by:

isEmpty in interface Queue<E>

Returns:

true if the queue is empty, false otherwise.

main

public static void main(java.lang.String[] args)

Test program that performs a series of operations on on a queue and prints the operation performed, the returned element and the content of the stack after each operation.

size

public int size()

Description copied from interface: Queue

Returns the number of elements in the queue.

Specified by:

size in interface Queue<E>

Returns:

number of elements in the queue.

status

public static void status(Queue Q,
                          java.lang.String op,
                          java.lang.Object element)

Prints information about an operation and the queue.

Parameters:

op - operation performed

element - element returned by the operation

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object