Shuyi Chen | d7955ce | 2013-05-22 14:51:55 -0700 | [diff] [blame] | 1 | /** |
| 2 | * $RCSfile$ |
| 3 | * $Revision: 2779 $ |
| 4 | * $Date: 2005-09-05 17:00:45 -0300 (Mon, 05 Sep 2005) $ |
| 5 | * |
| 6 | * Copyright 2003-2006 Jive Software. |
| 7 | * |
| 8 | * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License"); |
| 9 | * you may not use this file except in compliance with the License. |
| 10 | * You may obtain a copy of the License at |
| 11 | * |
| 12 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 13 | * |
| 14 | * Unless required by applicable law or agreed to in writing, software |
| 15 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 16 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 17 | * See the License for the specific language governing permissions and |
| 18 | * limitations under the License. |
| 19 | */ |
| 20 | |
| 21 | package org.jivesoftware.smackx.muc; |
| 22 | |
| 23 | import java.util.concurrent.ArrayBlockingQueue; |
| 24 | import java.util.concurrent.TimeUnit; |
| 25 | |
| 26 | import org.jivesoftware.smack.SmackConfiguration; |
| 27 | import org.jivesoftware.smack.packet.Packet; |
| 28 | |
| 29 | /** |
| 30 | * A variant of the {@link org.jivesoftware.smack.PacketCollector} class |
| 31 | * that does not force attachment to a <code>Connection</code> |
| 32 | * on creation and no filter is required. Used to collect message |
| 33 | * packets targeted to a group chat room. |
| 34 | * |
| 35 | * @author Larry Kirschner |
| 36 | */ |
| 37 | class ConnectionDetachedPacketCollector { |
| 38 | /** |
| 39 | * Max number of packets that any one collector can hold. After the max is |
| 40 | * reached, older packets will be automatically dropped from the queue as |
| 41 | * new packets are added. |
| 42 | */ |
| 43 | private int maxPackets = SmackConfiguration.getPacketCollectorSize(); |
| 44 | |
| 45 | private ArrayBlockingQueue<Packet> resultQueue; |
| 46 | |
| 47 | /** |
| 48 | * Creates a new packet collector. If the packet filter is <tt>null</tt>, then |
| 49 | * all packets will match this collector. |
| 50 | */ |
| 51 | public ConnectionDetachedPacketCollector() { |
| 52 | this(SmackConfiguration.getPacketCollectorSize()); |
| 53 | } |
| 54 | |
| 55 | /** |
| 56 | * Creates a new packet collector. If the packet filter is <tt>null</tt>, then |
| 57 | * all packets will match this collector. |
| 58 | */ |
| 59 | public ConnectionDetachedPacketCollector(int maxSize) { |
| 60 | this.resultQueue = new ArrayBlockingQueue<Packet>(maxSize); |
| 61 | } |
| 62 | |
| 63 | /** |
| 64 | * Polls to see if a packet is currently available and returns it, or |
| 65 | * immediately returns <tt>null</tt> if no packets are currently in the |
| 66 | * result queue. |
| 67 | * |
| 68 | * @return the next packet result, or <tt>null</tt> if there are no more |
| 69 | * results. |
| 70 | */ |
| 71 | public Packet pollResult() { |
| 72 | return resultQueue.poll(); |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * Returns the next available packet. The method call will block (not return) |
| 77 | * until a packet is available. |
| 78 | * |
| 79 | * @return the next available packet. |
| 80 | */ |
| 81 | public Packet nextResult() { |
| 82 | try { |
| 83 | return resultQueue.take(); |
| 84 | } |
| 85 | catch (InterruptedException e) { |
| 86 | throw new RuntimeException(e); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | /** |
| 91 | * Returns the next available packet. The method call will block (not return) |
| 92 | * until a packet is available or the <tt>timeout</tt> has elapased. If the |
| 93 | * timeout elapses without a result, <tt>null</tt> will be returned. |
| 94 | * |
| 95 | * @param timeout the amount of time to wait for the next packet (in milleseconds). |
| 96 | * @return the next available packet. |
| 97 | */ |
| 98 | public Packet nextResult(long timeout) { |
| 99 | try { |
| 100 | return resultQueue.poll(timeout, TimeUnit.MILLISECONDS); |
| 101 | } |
| 102 | catch (InterruptedException e) { |
| 103 | throw new RuntimeException(e); |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * Processes a packet to see if it meets the criteria for this packet collector. |
| 109 | * If so, the packet is added to the result queue. |
| 110 | * |
| 111 | * @param packet the packet to process. |
| 112 | */ |
| 113 | protected void processPacket(Packet packet) { |
| 114 | if (packet == null) { |
| 115 | return; |
| 116 | } |
| 117 | |
| 118 | while (!resultQueue.offer(packet)) { |
| 119 | // Since we know the queue is full, this poll should never actually block. |
| 120 | resultQueue.poll(); |
| 121 | } |
| 122 | } |
| 123 | } |