regionQueue
Class ClientQueue

java.lang.Object
  java.util.AbstractCollection
      com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractCollection
          com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractQueue
              regionQueue.ClientQueue

All Implemented Interfaces:

com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue, com.gemstone.bp.edu.emory.mathcs.backport.java.util.Queue, Iterable, Collection

public class ClientQueue
extends com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractQueue
implements com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

The client side of a distributed queue. A ClientQueue implements the BlockingQueue interface and delegates its work to a RegionQueue that is hosted by a ServerQueue.

Since:

4.1

Author:

GemStone Systems, Inc.

Field Summary

protected String	id The id of this VM
(package private) static String	INSERT_PREFIX This is the key of the region element used for adding elements to the queue.
(package private) static Object	IS_EMPTY An argument to a Region get() that denotes that it is an "is empty" operation.
protected static long	nextRequestId The next request id to use when getting an element from the server queue.
(package private) static Object	PEEK An argument to a Region get() that denotes that it is a peek operation.
(package private) static Object	PUT An argument to a Region put() that denotes that it is a (queue) put operation.
(package private) static Object	REMAINING_CAPACITY An argument to a Region get() that denotes that it is a "remaining capacity" operation.
(package private) static Object	SIZE An argument to a Region get() that denotes that it is a size operation.
(package private) static Object	TAKE An argument to a Region get() that denotes that it is a take operation.
(package private) static Object	TO_ARRAY An argument to a Region get() that denotes that it is a "to array" operation.

Constructor Summary

ClientQueue(String name, String[] hosts, int[] ports)
Creates a new ClientQueue that will access queues hosted by the given servers.

Method Summary

void	close() Closes this ClientQueue and releases all resources associated with it including the communication Region
int	drainTo(Collection c) Throws an UnsupportedOperationException
int	drainTo(Collection c, int maxElements) Throws an UnsupportedOperationException
String	getName()
boolean	isEmpty()
Iterator	iterator() Throws an UnsupportedOperationException
static void	main(String[] args) Main program that creates a ClientQueue and allows the user to interact with it via the console.
boolean	offer(Object o)
boolean	offer(Object o, long timeout, com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.TimeUnit unit)
Object	peek()
Object	poll()
Object	poll(long timeout, com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.TimeUnit unit)
void	put(Object o)
int	remainingCapacity()
int	size()
Object	take()
Object[]	toArray()
Object[]	toArray(Object[] array)
String	toString()

Methods inherited from class com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractQueue

add, addAll, clear, element, remove

Methods inherited from class java.util.AbstractCollection

contains, containsAll, remove, removeAll, retainAll

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

add, contains, remove

Methods inherited from interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.Queue

element, remove

Methods inherited from interface java.util.Collection

addAll, clear, containsAll, equals, hashCode, removeAll, retainAll

Field Detail

PEEK

static Object PEEK

An argument to a Region get() that denotes that it is a peek operation.

TAKE

static Object TAKE

An argument to a Region get() that denotes that it is a take operation.

PUT

static Object PUT

An argument to a Region put() that denotes that it is a (queue) put operation.

IS_EMPTY

static Object IS_EMPTY

An argument to a Region get() that denotes that it is an "is empty" operation.

SIZE

static Object SIZE

An argument to a Region get() that denotes that it is a size operation.

REMAINING_CAPACITY

static Object REMAINING_CAPACITY

An argument to a Region get() that denotes that it is a "remaining capacity" operation.

TO_ARRAY

static Object TO_ARRAY

An argument to a Region get() that denotes that it is a "to array" operation.

nextRequestId

protected static long nextRequestId

The next request id to use when getting an element from the server queue.

id

protected String id

The id of this VM

INSERT_PREFIX

static String INSERT_PREFIX

This is the key of the region element used for adding elements to the queue. Its uniqueness is required to prevent deadlock on the Cache server.

Constructor Detail

ClientQueue

public ClientQueue(String name,
                   String[] hosts,
                   int[] ports)
            throws TimeoutException

Creates a new ClientQueue that will access queues hosted by the given servers.

Parameters:

name - The name of the distributed queue

hosts - The host(s) on which the server queue(s) reside

ports - The port(s) through which the server queue(s) are accessed.

Throws:

TimeoutException - If a cache access times out which creating the client queue

IllegalStateException - If the state of the cache prevents the client queue from being created

Method Detail

close

public void close()

Closes this ClientQueue and releases all resources associated with it including the communication Region

put

public void put(Object o)
         throws InterruptedException

Specified by:

put in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

Throws:

InterruptedException

take

public Object take()
            throws InterruptedException

Specified by:

take in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

Throws:

InterruptedException

peek

public Object peek()

Specified by:

peek in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.Queue

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Collection

Overrides:

isEmpty in class AbstractCollection

poll

public Object poll()

Specified by:

poll in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.Queue

size

public int size()

Specified by:

size in interface Collection

Specified by:

size in class AbstractCollection

toArray

public Object[] toArray(Object[] array)

Specified by:

toArray in interface Collection

Overrides:

toArray in class com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractCollection

toArray

public Object[] toArray()

Specified by:

toArray in interface Collection

Overrides:

toArray in class com.gemstone.bp.edu.emory.mathcs.backport.java.util.AbstractCollection

poll

public Object poll(long timeout,
                   com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.TimeUnit unit)
            throws InterruptedException

Specified by:

poll in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

Throws:

InterruptedException

offer

public boolean offer(Object o)

Specified by:

offer in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

Specified by:

offer in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.Queue

offer

public boolean offer(Object o,
                     long timeout,
                     com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.TimeUnit unit)
              throws InterruptedException

Specified by:

offer in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

Throws:

InterruptedException

remainingCapacity

public int remainingCapacity()

Specified by:

remainingCapacity in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

iterator

public Iterator iterator()

Throws an UnsupportedOperationException

Specified by:

iterator in interface Iterable

Specified by:

iterator in interface Collection

Specified by:

iterator in class AbstractCollection

drainTo

public int drainTo(Collection c)

Throws an UnsupportedOperationException

Specified by:

drainTo in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

drainTo

public int drainTo(Collection c,
                   int maxElements)

Throws an UnsupportedOperationException

Specified by:

drainTo in interface com.gemstone.bp.edu.emory.mathcs.backport.java.util.concurrent.BlockingQueue

getName

public String getName()

toString

public String toString()

Overrides:

toString in class AbstractCollection

main

public static void main(String[] args)
                 throws Throwable

Main program that creates a ClientQueue and allows the user to interact with it via the console.

Throws:

Throwable