cs101.util.queue
Interface Queue

All Known Implementing Classes:

DefaultQueue

public interface Queue

Generic Queue Interface. Allows insertion/deletion at either end.

Copyright (c) 1998 Massachusetts Institute of Technology

Version:

$Id: Queue.java,v 1.1.1.1 2002/06/05 21:56:32 root Exp $

Author:

Todd C. Parnell, tparnell@ai.mit.edu

Field Summary

static int	BACK
static int	FRONT

Method Summary

java.lang.Object	dequeue() Removes and returns the Object at the tail of the queue.
java.lang.Object	dequeue(int end) Removes and returns the Object at the specified end of the queue.
java.util.Enumeration	elements() Returns an Enumeration of the Objects in the queue.
void	enqueue(java.lang.Object obj) Puts obj into the front the queue.
void	enqueue(java.lang.Object obj, int end) Puts obj into the specified end of the queue.
boolean	isEmpty() Tests whether the queue is empty.
java.lang.Object	peek() Gets the tail object from the queue without removing it.
java.lang.Object	peek(int end) Gets the object from the specified end of the queue without removing it.
int	size() Returns the number of elements in this.

Field Detail

FRONT

public static final int FRONT

See Also:

Constant Field Values

BACK

public static final int BACK

See Also:

Constant Field Values

Method Detail

size

public int size()

Returns the number of elements in this.

peek

public java.lang.Object peek()

Gets the tail object from the queue without removing it.

peek

public java.lang.Object peek(int end)

Gets the object from the specified end of the queue without removing it.

enqueue

public void enqueue(java.lang.Object obj)

Puts obj into the front the queue.

enqueue

public void enqueue(java.lang.Object obj,
                    int end)

Puts obj into the specified end of the queue.

dequeue

public java.lang.Object dequeue()

Removes and returns the Object at the tail of the queue.

dequeue

public java.lang.Object dequeue(int end)

Removes and returns the Object at the specified end of the queue.

isEmpty

public boolean isEmpty()

Tests whether the queue is empty.

elements

public java.util.Enumeration elements()

Returns an Enumeration of the Objects in the queue.

Note: Do not modify the queue while enumerating--unpredictable behavior may result.

See Also:

Enumeration