ibis.util
Class Queue

java.lang.Object
  ibis.util.Queue

public class Queue

extends java.lang.Object

A simple queue class. Objects can be enqueued, dequeued, or dequeued with a deadline.

Constructor Summary

Queue()
Constructs a new queue.

Method Summary

java.lang.Object	dequeue() Dequeues the head of the queue.
java.lang.Object	dequeue(long deadline) Dequeues the head of the queue.
void	enqueue(java.lang.Object o) Enqueues the specified object, and notifies: if there are threads waiting, a single one is notified.
int	size() Returns the length of the queue.

Methods inherited from class java.lang.Object

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

Constructor Detail

Queue

public Queue()

Constructs a new queue.

Method Detail

enqueue

public void enqueue(java.lang.Object o)

Enqueues the specified object, and notifies: if there are threads waiting, a single one is notified.

Parameters:

o - the object to be enqueued.

dequeue

public java.lang.Object dequeue()

Dequeues the head of the queue. If the queue is empty it will wait until something is added to the queue.

Returns:

the dequeued object.

dequeue

public java.lang.Object dequeue(long deadline)

Dequeues the head of the queue. If the queue is empty it will wait until something is added to the queue, or the deadline has passed.

Parameters:

deadline - the deadline expressed in milliseconds since 1-1-1970. a value of "0" will cause this function to wait forever, on -1 it will not wait at all.

Returns:

the dequeued object, or null if the deadline passed

size

public int size()

Returns the length of the queue.

Returns:

the length of the queue.