/*
* Copyright 1999-2011 Alibaba Group.
*
* 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 com.alibaba.dubbo.remoting.transport.mina;
import java.io.IOException;
import org.apache.mina.common.ByteBuffer;
import org.apache.mina.common.IoSession;
import org.apache.mina.filter.codec.ProtocolCodecFactory;
import org.apache.mina.filter.codec.ProtocolDecoder;
import org.apache.mina.filter.codec.ProtocolDecoderOutput;
import org.apache.mina.filter.codec.ProtocolEncoder;
import org.apache.mina.filter.codec.ProtocolEncoderOutput;
import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.URL;
import com.alibaba.dubbo.common.io.Bytes;
import com.alibaba.dubbo.common.io.UnsafeByteArrayInputStream;
import com.alibaba.dubbo.common.io.UnsafeByteArrayOutputStream;
import com.alibaba.dubbo.remoting.Channel;
import com.alibaba.dubbo.remoting.ChannelHandler;
import com.alibaba.dubbo.remoting.Codec;
import com.alibaba.dubbo.remoting.exchange.Response;
/**
* MinaCodecAdapter.
*
* @author qian.lei
*/
final class MinaCodecAdapter implements ProtocolCodecFactory {
private static final String BUFFER_KEY = MinaCodecAdapter.class.getName() + ".BUFFER";
private final ProtocolEncoder encoder = new InternalEncoder();
private final ProtocolDecoder decoder = new InternalDecoder();
private final Codec upstreamCodec;
private final Codec downstreamCodec;
private final URL url;
private final ChannelHandler handler;
private final int bufferSize;
public MinaCodecAdapter(Codec codec, URL url, ChannelHandler handler){
this(codec,codec,url,handler);
}
/**
* server 端如果有消息发送需要分开codec，默认的上行code是dubbo1兼容的
*/
public MinaCodecAdapter(Codec upstreamCodec, Codec downstreamCodec, URL url, ChannelHandler handler){
this.upstreamCodec = upstreamCodec;
this.downstreamCodec = downstreamCodec;
this.url = url;
this.handler = handler;
int b = url.getPositiveParameter(Constants.BUFFER_KEY, Constants.DEFAULT_BUFFER_SIZE);
this.bufferSize = b >= Constants.MIN_BUFFER_SIZE && b <= Constants.MAX_BUFFER_SIZE ? b : Constants.DEFAULT_BUFFER_SIZE;
}
public ProtocolEncoder getEncoder() {
return encoder;
}
public ProtocolDecoder getDecoder() {
return decoder;
}
private class InternalEncoder implements ProtocolEncoder {
public void dispose(IoSession session) throws Exception {
}
public void encode(IoSession session, Object msg, ProtocolEncoderOutput out) throws Exception {
UnsafeByteArrayOutputStream os = new UnsafeByteArrayOutputStream(1024); // 不需要关闭
MinaChannel channel = MinaChannel.getOrAddChannel(session, url, handler);
try {
if(!(msg instanceof Response)){
downstreamCodec.encode(channel, os, msg);
}else{
upstreamCodec.encode(channel, os, msg);
}
} finally {
MinaChannel.removeChannelIfDisconnectd(session);
}
out.write(ByteBuffer.wrap(os.toByteArray()));
out.flush();
}
}
private class InternalDecoder implements ProtocolDecoder {
public void decode(IoSession session, ByteBuffer in, ProtocolDecoderOutput out) throws Exception {
int readable = in.limit();
if (readable <= 0) return;
int off, limit;
byte[] buf;
// load buffer from context.
Object[] tmp = (Object[]) session.getAttribute(BUFFER_KEY);
if (tmp == null) {
buf = new byte[bufferSize];
off = limit = 0;
} else {
buf = (byte[]) tmp[0];
off = (Integer) tmp[1];
limit = (Integer) tmp[2];
}
Channel channel = MinaChannel.getOrAddChannel(session, url, handler);
boolean remaining = true;
Object msg;
UnsafeByteArrayInputStream bis;
try {
do {
// read data into buffer.
int read = Math.min(readable, buf.length - limit);
in.get(buf, limit, read);
limit += read;
readable -= read;
bis = new UnsafeByteArrayInputStream(buf, off, limit - off); // 不需要关闭
// decode object.
do {
try {
msg = upstreamCodec.decode(channel, bis);
} catch (IOException e) {
remaining = false;
throw e;
}
if (msg == Codec.NEED_MORE_INPUT) {
if (off == 0) {
if (readable > 0) {
buf = Bytes.copyOf(buf, buf.length << 1);
}
} else {
int len = limit - off;
System.arraycopy(buf, off, buf, 0, len);
off = 0;
limit = len;
}
break;
} else {
int pos = bis.position();
if (pos == off) {
remaining = false;
throw new IOException("Decode without read data.");
}
if (msg != null) {
out.write(msg);
}
off = pos;
}
} while (bis.available() > 0);
} while (readable > 0);
} finally {
if (remaining) {
int len = limit - off;
if (len < buf.length / 2) {
System.arraycopy(buf, off, buf, 0, len);
off = 0;
limit = len;
}
session.setAttribute(BUFFER_KEY, new Object[] { buf, off, limit });
} else {
session.removeAttribute(BUFFER_KEY);
}
MinaChannel.removeChannelIfDisconnectd(session);
}
}
public void dispose(IoSession session) throws Exception {
}
public void finishDecode(IoSession session, ProtocolDecoderOutput out) throws Exception {
}
}
}