iofilterchainbuilder.java

mina是以Java实现的一个开源的网络程序框架

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 *  Licensed to the Apache Software Foundation (ASF) under one
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 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
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 *  KIND, either express or implied.  See the License for the
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package org.apache.mina.core.filterchain;

import org.apache.mina.core.session.IoSession;

/**
 * An interface that builds {@link IoFilterChain} in predefined way
 * when {@link IoSession} is created.  You can extract common filter chain
 * modification logic to this interface.  For example, to add a filter
 * to the chain,
 * <pre>
 * public class MyFilterChainBuilder implements IoFilterChainBuilder {
 *     public void buildFilterChain( IoFilterChain chain ) throws Exception {
 *         chain.addLast( "myFilter", new MyFilter() );
 *     }
 * }
 * </pre>
 *
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 576217 $, $Date: 2007-09-17 01:55:27 +0200 (Mon, 17 Sep 2007) $
 */
public interface IoFilterChainBuilder {
    /**
     * An implementation which does nothing.
     */
    IoFilterChainBuilder NOOP = new IoFilterChainBuilder() {
        public void buildFilterChain(IoFilterChain chain) throws Exception {
        }

        @Override
        public String toString() {
            return "NOOP";
        }
    };

    /**
     * Modifies the specified <tt>chain</tt>.
     */
    void buildFilterChain(IoFilterChain chain) throws Exception;
}