001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *
010 *    http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License.
018 *
019 */
020package org.apache.mina.filter.buffer;
021
022import org.apache.mina.core.buffer.IoBuffer;
023import org.apache.mina.util.LazyInitializer;
024
025/**
026 * An {@link LazyInitializer} implementation that initializes an 
027 * {@link IoBuffer} only when needed.
028 * 
029 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
030 * @since MINA 2.0.0-M2
031 */
032public class IoBufferLazyInitializer extends LazyInitializer<IoBuffer> {
033
034    /**
035     * The buffer size allocated for each new session's buffer.
036     */
037    private int bufferSize;
038
039    /**
040     * Constructor which sets allocated buffer size to <code>bufferSize</code>.
041     * 
042     * @param bufferSize the new buffer size
043     */
044    public IoBufferLazyInitializer(int bufferSize) {
045        this.bufferSize = bufferSize;
046    }
047
048    /**
049     * {@inheritDoc}
050     */
051    public IoBuffer init() {
052        return IoBuffer.allocate(bufferSize);
053    }
054}