001 /*
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements. See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership. The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License. You may obtain a copy of the License at
010 *
011 * http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing,
014 * software distributed under the License is distributed on an
015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
016 * KIND, either express or implied. See the License for the
017 * specific language governing permissions and limitations
018 * under the License.
019 *
020 */
021 package org.apache.qpid.pool;
022
023 import org.apache.mina.common.IoFilterChain;
024 import org.apache.mina.common.ThreadModel;
025 import org.apache.mina.filter.ReferenceCountingIoFilter;
026
027 /**
028 * ReadWriteThreadModel is a Mina i/o filter chain factory, which creates a filter chain with seperate filters to
029 * handle read and write events. The seperate filters are {@link PoolingFilter}s, which have thread pools to handle
030 * these events. The effect of this is that reading and writing may happen concurrently.
031 *
032 * <p/>Socket i/o will only happen with concurrent reads and writes if Mina has seperate selector threads for each.
033 *
034 * <p/><table id="crc"><caption>CRC Card</caption>
035 * <tr><th> Responsibilities <th> Collaborations
036 * <tr><td> Create a filter chain with seperate read and write thread pools for read/write Mina events.
037 * <td> {@link PoolingFilter}
038 * </table>
039 */
040 public class ReadWriteThreadModel implements ThreadModel
041 {
042 /** Holds the singleton instance of this factory. */
043 private static final ReadWriteThreadModel _instance = new ReadWriteThreadModel();
044
045 /** Holds the thread pooling filter for reads. */
046 private final PoolingFilter _asynchronousReadFilter;
047
048 /** Holds the thread pooloing filter for writes. */
049 private final PoolingFilter _asynchronousWriteFilter;
050
051 /**
052 * Creates a new factory for concurrent i/o, thread pooling filter chain construction. This is private, so that
053 * only a singleton instance of the factory is ever created.
054 */
055 private ReadWriteThreadModel()
056 {
057 final ReferenceCountingExecutorService executor = ReferenceCountingExecutorService.getInstance();
058 _asynchronousReadFilter = PoolingFilter.createAynschReadPoolingFilter(executor, "AsynchronousReadFilter");
059 _asynchronousWriteFilter = PoolingFilter.createAynschWritePoolingFilter(executor, "AsynchronousWriteFilter");
060 }
061
062 /**
063 * Gets the singleton instance of this filter chain factory.
064 *
065 * @return The singleton instance of this filter chain factory.
066 */
067 public static ReadWriteThreadModel getInstance()
068 {
069 return _instance;
070 }
071
072 /**
073 * Gets the read filter.
074 *
075 * @return The read filter.
076 */
077 public PoolingFilter getAsynchronousReadFilter()
078 {
079 return _asynchronousReadFilter;
080 }
081
082 /**
083 * Gets the write filter.
084 *
085 * @return The write filter.
086 */
087 public PoolingFilter getAsynchronousWriteFilter()
088 {
089 return _asynchronousWriteFilter;
090 }
091
092 /**
093 * Adds the concurrent read and write filters to a filter chain.
094 *
095 * @param chain The Mina filter chain to add to.
096 */
097 public void buildFilterChain(IoFilterChain chain)
098 {
099 chain.addFirst("AsynchronousReadFilter", new ReferenceCountingIoFilter(_asynchronousReadFilter));
100 chain.addLast("AsynchronousWriteFilter", new ReferenceCountingIoFilter(_asynchronousWriteFilter));
101 }
102 }
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