textlineencoder.java

利用mina框架写的一个通信实例。初学者的一个好教程。

/*
 *   @(#) $Id: TextLineEncoder.java 357871 2005-12-20 01:56:40Z trustin $
 *
 *   Copyright 2004 The Apache Software Foundation
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       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 "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 *
 */
package org.apache.mina.examples.reverser;

import org.apache.mina.common.ByteBuffer;
import org.apache.mina.protocol.ProtocolEncoder;
import org.apache.mina.protocol.ProtocolEncoderOutput;
import org.apache.mina.protocol.ProtocolSession;
import org.apache.mina.protocol.ProtocolViolationException;

/**
 * Encodes a string into a text line which ends with <code>"\r\n"</code>.
 * 
 * @author The Apache Directory Project ([e-mail])
 * @version $Rev: 357871 $, $Date: 2005-12-20 10:56:40 +0900 (Tue, 20 Dec 2005) $,
 */
public class TextLineEncoder implements ProtocolEncoder {

	public void encode(ProtocolSession session, Object message,
			ProtocolEncoderOutput out) throws ProtocolViolationException {

		String val = message.toString();
		// Don't accept too long strings.
		if (val.length() > 256) {
			throw new ProtocolViolationException(
					"Cannot encode too long string.");
		}

		val += "\r\n";

		ByteBuffer buf = ByteBuffer.allocate(val.length());
		for (int i = 0; i < val.length(); i++) {
			buf.put((byte) val.charAt(i));
		}

		buf.flip();
		out.write(buf);

		throw new ProtocolViolationException("cuiyunhai");
	}
}