protected Object decode(Channel channel, ChannelBuffer buffer, int readable, byte[] header)
throws IOException {
// check magic number.
if (readable > 0 && header[0] != MAGIC_HIGH || readable > 1 && header[1] != MAGIC_LOW) {
int length = header.length;
if (header.length < readable) {
header = Bytes.copyOf(header, readable);
buffer.readBytes(header, length, readable - length);
}
for (int i = 1; i < header.length - 1; i++) {
if (header[i] == MAGIC_HIGH && header[i + 1] == MAGIC_LOW) {
buffer.readerIndex(buffer.readerIndex() - header.length + i);
header = Bytes.copyOf(header, i);
break;
}
}
return super.decode(channel, buffer, readable, header);
}
// check length.
if (readable < HEADER_LENGTH) {
return DecodeResult.NEED_MORE_INPUT;
}
// get data length.
int len = Bytes.bytes2int(header, 12);
checkPayload(channel, len);
int tt = len + HEADER_LENGTH;
if (readable < tt) {
return DecodeResult.NEED_MORE_INPUT;
}
// limit input stream.
ChannelBufferInputStream is = new ChannelBufferInputStream(buffer, len);
try {
return decodeBody(channel, is, header);
} finally {
if (is.available() > 0) {
try {
if (logger.isWarnEnabled()) {
logger.warn("Skip input stream " + is.available());
}
StreamUtils.skipUnusedStream(is);
} catch (IOException e) {
logger.warn(e.getMessage(), e);
}
}
}
}
protected Object decodeBody(Channel channel, InputStream is, byte[] header) throws IOException {
byte flag = header[2], proto = (byte) (flag & SERIALIZATION_MASK);
Serialization s = CodecSupport.getSerialization(channel.getUrl(), proto);
ObjectInput in = s.deserialize(channel.getUrl(), is);
// get request id.
long id = Bytes.bytes2long(header, 4);
if ((flag & FLAG_REQUEST) == 0) {
// decode response.
Response res = new Response(id);
if ((flag & FLAG_EVENT) != 0) {
res.setEvent(Response.HEARTBEAT_EVENT);
}
// get status.
byte status = header[3];
res.setStatus(status);
if (status == Response.OK) {
try {
Object data;
if (res.isHeartbeat()) {
data = decodeHeartbeatData(channel, in);
} else if (res.isEvent()) {
data = decodeEventData(channel, in);
} else {
data = decodeResponseData(channel, in, getRequestData(id));
}
res.setResult(data);
} catch (Throwable t) {
res.setStatus(Response.CLIENT_ERROR);
res.setErrorMessage(StringUtils.toString(t));
}
} else {
res.setErrorMessage(in.readUTF());
}
return res;
} else {
// decode request.
Request req = new Request(id);
req.setVersion("2.0.0");
req.setTwoWay((flag & FLAG_TWOWAY) != 0);
if ((flag & FLAG_EVENT) != 0) {
req.setEvent(Request.HEARTBEAT_EVENT);
}
try {
Object data;
if (req.isHeartbeat()) {
data = decodeHeartbeatData(channel, in);
} else if (req.isEvent()) {
data = decodeEventData(channel, in);
} else {
data = decodeRequestData(channel, in);
}
req.setData(data);
} catch (Throwable t) {
// bad request
req.setBroken(true);
req.setData(t);
}
return req;
}
}
protected void encodeRequest(Channel channel, ChannelBuffer buffer, Request req)
throws IOException {
Serialization serialization = getSerialization(channel);
// header.
byte[] header = new byte[HEADER_LENGTH];
// set magic number.
Bytes.short2bytes(MAGIC, header);
// set request and serialization flag.
header[2] = (byte) (FLAG_REQUEST | serialization.getContentTypeId());
if (req.isTwoWay()) header[2] |= FLAG_TWOWAY;
if (req.isEvent()) header[2] |= FLAG_EVENT;
// set request id.
Bytes.long2bytes(req.getId(), header, 4);
// encode request data.
int savedWriteIndex = buffer.writerIndex();
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH);
ChannelBufferOutputStream bos = new ChannelBufferOutputStream(buffer);
ObjectOutput out = serialization.serialize(channel.getUrl(), bos);
try {
if (req.isEvent()) {
encodeEventData(channel, out, req.getData());
} else {
encodeRequestData(channel, out, req.getData());
}
out.flushBuffer();
} finally {
// modified by lishen
if (out instanceof Cleanable) {
((Cleanable) out).cleanup();
}
}
bos.flush();
bos.close();
int len = bos.writtenBytes();
checkPayload(channel, len);
Bytes.int2bytes(len, header, 12);
// write
buffer.writerIndex(savedWriteIndex);
buffer.writeBytes(header); // write header.
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH + len);
}
/*
* 接收
*
* @param context 上下文
* @param channel 通道
* @param buffer 缓存
* @param readable 缓存可读
* @param bytes 输入缓存
* @param offset 指向已读数据的偏移量，off之前的数据都是已用过的
* @param limit 有效长度，limit之后的长度是空白或无效数据，off到limit之间的数据是准备使用的数据
* @return 后续动作
* @throws IOException
*/
private NextAction receive(
FilterChainContext context,
Channel channel,
Buffer buffer,
int readable,
byte[] bytes,
int offset,
int limit)
throws IOException {
for (; ; ) {
int read = Math.min(readable, bytes.length - limit); // 取bytes缓存空闲区，和可读取新数据，的最小值，即：此次最多读写数据的大小
buffer.get(bytes, limit, read); // 从可读取新数据中，读取数据，尽量填满bytes缓存空闲区
limit += read; // 有效数据变长
readable -= read; // 可读数据变少
UnsafeByteArrayInputStream input =
new UnsafeByteArrayInputStream(
bytes, offset, limit - offset); // 将bytes缓存转成InputStream，不需要关闭
Object msg = upstreamCodec.decode(channel, input); // 调用Codec接口，解码数据
if (msg == Codec.NEED_MORE_INPUT) { // 如果Codec觉得数据不够，不足以解码成一个对象
if (readable == 0) { // 如果没有更多可读数据
channel.setAttribute(
BUFFER_KEY, new Object[] {bytes, offset, limit}); // 放入通道属性中，等待下一个Buffer的到来
return context.getStopAction();
} else { // 扩充或挪出空闲区，并循环，直到可读数据都加载到bytes缓存
if (offset == 0) { // 如果bytes缓存全部没有被使用，如果这时数据还不够
bytes = Bytes.copyOf(bytes, bytes.length << 1); // 将bytes缓存扩大一倍
} else { // 如果bytes缓存有一段数据已被使用
int len = limit - offset; // 计算有效数据长度
System.arraycopy(
bytes, offset, bytes, 0, len); // 将数据向前移到，压缩到已使用的部分，这样limit后面就会多出一些空闲，可以放数据
offset = 0; // 移到后，bytes缓存没有数据被使用
limit = len; // 移到后，有效数据都在bytes缓存最前面
}
}
} else { // 如果解析出一个结果
int position = input.position(); // 记录InputStream用了多少
if (position == offset) { // 如果InputStream没有被读过，就返回了数据，直接报错，否则InputStream永远读不完，会死递归
throw new IOException("Decode without read data.");
}
offset = position; // 记录已读数据
context.setMessage(msg); // 将消息改为解码后的对象，以便被后面的Filter使用。
if (limit - offset > 0 || readable > 0) { // 如果有效数据没有被读完，或者Buffer区还有未读数据
return context.getInvokeAction(
new Object[] {
buffer, readable, bytes, offset, limit
}); // 正常执行完Filter，并重新发起一轮Filter，继续读
} else { // 否则所有数据读完
return context.getInvokeAction(); // 正常执行完Filter
}
}
}
}
/**
* ExchangeCodec.
*
* @author qianlei
* @author william.liangf
*/
public class ExchangeCodec extends TelnetCodec {
private static final Logger logger = LoggerFactory.getLogger(ExchangeCodec.class);
// header length.
protected static final int HEADER_LENGTH = 16;
// magic header.
protected static final short MAGIC = (short) 0xdabb;
protected static final byte MAGIC_HIGH = Bytes.short2bytes(MAGIC)[0];
protected static final byte MAGIC_LOW = Bytes.short2bytes(MAGIC)[1];
// message flag.
protected static final byte FLAG_REQUEST = (byte) 0x80;
protected static final byte FLAG_TWOWAY = (byte) 0x40;
protected static final byte FLAG_EVENT = (byte) 0x20;
protected static final int SERIALIZATION_MASK = 0x1f;
public Short getMagicCode() {
return MAGIC;
}
public void encode(Channel channel, ChannelBuffer buffer, Object msg) throws IOException {
if (msg instanceof Request) {
encodeRequest(channel, buffer, (Request) msg);
} else if (msg instanceof Response) {
encodeResponse(channel, buffer, (Response) msg);
} else {
super.encode(channel, buffer, msg);
}
// TODO modified by lishen
// System.out.println(">>>>>>>>>>>>>>>>>>>>>> the resulting byte size of encoding is " +
// buffer.readableBytes());
if (logger.isTraceEnabled()) {
logger.trace("the resulting byte size of encoding is " + buffer.readableBytes());
}
}
public Object decode(Channel channel, ChannelBuffer buffer) throws IOException {
int readable = buffer.readableBytes();
byte[] header = new byte[Math.min(readable, HEADER_LENGTH)];
buffer.readBytes(header);
return decode(channel, buffer, readable, header);
}
protected Object decode(Channel channel, ChannelBuffer buffer, int readable, byte[] header)
throws IOException {
// check magic number.
if (readable > 0 && header[0] != MAGIC_HIGH || readable > 1 && header[1] != MAGIC_LOW) {
int length = header.length;
if (header.length < readable) {
header = Bytes.copyOf(header, readable);
buffer.readBytes(header, length, readable - length);
}
for (int i = 1; i < header.length - 1; i++) {
if (header[i] == MAGIC_HIGH && header[i + 1] == MAGIC_LOW) {
buffer.readerIndex(buffer.readerIndex() - header.length + i);
header = Bytes.copyOf(header, i);
break;
}
}
return super.decode(channel, buffer, readable, header);
}
// check length.
if (readable < HEADER_LENGTH) {
return DecodeResult.NEED_MORE_INPUT;
}
// get data length.
int len = Bytes.bytes2int(header, 12);
checkPayload(channel, len);
int tt = len + HEADER_LENGTH;
if (readable < tt) {
return DecodeResult.NEED_MORE_INPUT;
}
// limit input stream.
ChannelBufferInputStream is = new ChannelBufferInputStream(buffer, len);
try {
return decodeBody(channel, is, header);
} finally {
if (is.available() > 0) {
try {
if (logger.isWarnEnabled()) {
logger.warn("Skip input stream " + is.available());
}
StreamUtils.skipUnusedStream(is);
} catch (IOException e) {
logger.warn(e.getMessage(), e);
}
}
}
}
protected Object decodeBody(Channel channel, InputStream is, byte[] header) throws IOException {
byte flag = header[2], proto = (byte) (flag & SERIALIZATION_MASK);
Serialization s = CodecSupport.getSerialization(channel.getUrl(), proto);
ObjectInput in = s.deserialize(channel.getUrl(), is);
// get request id.
long id = Bytes.bytes2long(header, 4);
if ((flag & FLAG_REQUEST) == 0) {
// decode response.
Response res = new Response(id);
if ((flag & FLAG_EVENT) != 0) {
res.setEvent(Response.HEARTBEAT_EVENT);
}
// get status.
byte status = header[3];
res.setStatus(status);
if (status == Response.OK) {
try {
Object data;
if (res.isHeartbeat()) {
data = decodeHeartbeatData(channel, in);
} else if (res.isEvent()) {
data = decodeEventData(channel, in);
} else {
data = decodeResponseData(channel, in, getRequestData(id));
}
res.setResult(data);
} catch (Throwable t) {
res.setStatus(Response.CLIENT_ERROR);
res.setErrorMessage(StringUtils.toString(t));
}
} else {
res.setErrorMessage(in.readUTF());
}
return res;
} else {
// decode request.
Request req = new Request(id);
req.setVersion("2.0.0");
req.setTwoWay((flag & FLAG_TWOWAY) != 0);
if ((flag & FLAG_EVENT) != 0) {
req.setEvent(Request.HEARTBEAT_EVENT);
}
try {
Object data;
if (req.isHeartbeat()) {
data = decodeHeartbeatData(channel, in);
} else if (req.isEvent()) {
data = decodeEventData(channel, in);
} else {
data = decodeRequestData(channel, in);
}
req.setData(data);
} catch (Throwable t) {
// bad request
req.setBroken(true);
req.setData(t);
}
return req;
}
}
protected Object getRequestData(long id) {
DefaultFuture future = DefaultFuture.getFuture(id);
if (future == null) return null;
Request req = future.getRequest();
if (req == null) return null;
return req.getData();
}
protected void encodeRequest(Channel channel, ChannelBuffer buffer, Request req)
throws IOException {
Serialization serialization = getSerialization(channel);
// header.
byte[] header = new byte[HEADER_LENGTH];
// set magic number.
Bytes.short2bytes(MAGIC, header);
// set request and serialization flag.
header[2] = (byte) (FLAG_REQUEST | serialization.getContentTypeId());
if (req.isTwoWay()) header[2] |= FLAG_TWOWAY;
if (req.isEvent()) header[2] |= FLAG_EVENT;
// set request id.
Bytes.long2bytes(req.getId(), header, 4);
// encode request data.
int savedWriteIndex = buffer.writerIndex();
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH);
ChannelBufferOutputStream bos = new ChannelBufferOutputStream(buffer);
ObjectOutput out = serialization.serialize(channel.getUrl(), bos);
try {
if (req.isEvent()) {
encodeEventData(channel, out, req.getData());
} else {
encodeRequestData(channel, out, req.getData());
}
out.flushBuffer();
} finally {
// modified by lishen
if (out instanceof Cleanable) {
((Cleanable) out).cleanup();
}
}
bos.flush();
bos.close();
int len = bos.writtenBytes();
checkPayload(channel, len);
Bytes.int2bytes(len, header, 12);
// write
buffer.writerIndex(savedWriteIndex);
buffer.writeBytes(header); // write header.
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH + len);
}
protected void encodeResponse(Channel channel, ChannelBuffer buffer, Response res)
throws IOException {
try {
Serialization serialization = getSerialization(channel);
// header.
byte[] header = new byte[HEADER_LENGTH];
// set magic number.
Bytes.short2bytes(MAGIC, header);
// set request and serialization flag.
header[2] = serialization.getContentTypeId();
if (res.isHeartbeat()) header[2] |= FLAG_EVENT;
// set response status.
byte status = res.getStatus();
header[3] = status;
// set request id.
Bytes.long2bytes(res.getId(), header, 4);
int savedWriteIndex = buffer.writerIndex();
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH);
ChannelBufferOutputStream bos = new ChannelBufferOutputStream(buffer);
ObjectOutput out = serialization.serialize(channel.getUrl(), bos);
try {
// encode response data or error message.
if (status == Response.OK) {
if (res.isHeartbeat()) {
encodeHeartbeatData(channel, out, res.getResult());
} else {
encodeResponseData(channel, out, res.getResult());
}
} else out.writeUTF(res.getErrorMessage());
out.flushBuffer();
} finally {
// modified by lishen
if (out instanceof Cleanable) {
((Cleanable) out).cleanup();
}
}
bos.flush();
bos.close();
int len = bos.writtenBytes();
checkPayload(channel, len);
Bytes.int2bytes(len, header, 12);
// write
buffer.writerIndex(savedWriteIndex);
buffer.writeBytes(header); // write header.
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH + len);
} catch (Throwable t) {
// 发送失败信息给Consumer，否则Consumer只能等超时了
if (!res.isEvent() && res.getStatus() != Response.BAD_RESPONSE) {
try {
// FIXME 在Codec中打印出错日志？在IoHanndler的caught中统一处理？
logger.warn(
"Fail to encode response: "
+ res
+ ", send bad_response info instead, cause: "
+ t.getMessage(),
t);
Response r = new Response(res.getId(), res.getVersion());
r.setStatus(Response.BAD_RESPONSE);
r.setErrorMessage(
"Failed to send response: " + res + ", cause: " + StringUtils.toString(t));
channel.send(r);
return;
} catch (RemotingException e) {
logger.warn(
"Failed to send bad_response info back: " + res + ", cause: " + e.getMessage(), e);
}
}
// 重新抛出收到的异常
if (t instanceof IOException) {
throw (IOException) t;
} else if (t instanceof RuntimeException) {
throw (RuntimeException) t;
} else if (t instanceof Error) {
throw (Error) t;
} else {
throw new RuntimeException(t.getMessage(), t);
}
}
}
@Override
protected Object decodeData(ObjectInput in) throws IOException {
return decodeRequestData(in);
}
@Deprecated
protected Object decodeHeartbeatData(ObjectInput in) throws IOException {
try {
return in.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(StringUtils.toString("Read object failed.", e));
}
}
protected Object decodeRequestData(ObjectInput in) throws IOException {
try {
return in.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(StringUtils.toString("Read object failed.", e));
}
}
protected Object decodeResponseData(ObjectInput in) throws IOException {
try {
return in.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(StringUtils.toString("Read object failed.", e));
}
}
@Override
protected void encodeData(ObjectOutput out, Object data) throws IOException {
encodeRequestData(out, data);
}
private void encodeEventData(ObjectOutput out, Object data) throws IOException {
out.writeObject(data);
}
@Deprecated
protected void encodeHeartbeatData(ObjectOutput out, Object data) throws IOException {
encodeEventData(out, data);
}
protected void encodeRequestData(ObjectOutput out, Object data) throws IOException {
out.writeObject(data);
}
protected void encodeResponseData(ObjectOutput out, Object data) throws IOException {
out.writeObject(data);
}
@Override
protected Object decodeData(Channel channel, ObjectInput in) throws IOException {
return decodeRequestData(channel, in);
}
protected Object decodeEventData(Channel channel, ObjectInput in) throws IOException {
try {
return in.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(StringUtils.toString("Read object failed.", e));
}
}
@Deprecated
protected Object decodeHeartbeatData(Channel channel, ObjectInput in) throws IOException {
try {
return in.readObject();
} catch (ClassNotFoundException e) {
throw new IOException(StringUtils.toString("Read object failed.", e));
}
}
protected Object decodeRequestData(Channel channel, ObjectInput in) throws IOException {
return decodeRequestData(in);
}
protected Object decodeResponseData(Channel channel, ObjectInput in) throws IOException {
return decodeResponseData(in);
}
protected Object decodeResponseData(Channel channel, ObjectInput in, Object requestData)
throws IOException {
return decodeResponseData(channel, in);
}
@Override
protected void encodeData(Channel channel, ObjectOutput out, Object data) throws IOException {
encodeRequestData(channel, out, data);
}
private void encodeEventData(Channel channel, ObjectOutput out, Object data) throws IOException {
encodeEventData(out, data);
}
@Deprecated
protected void encodeHeartbeatData(Channel channel, ObjectOutput out, Object data)
throws IOException {
encodeHeartbeatData(out, data);
}
protected void encodeRequestData(Channel channel, ObjectOutput out, Object data)
throws IOException {
encodeRequestData(out, data);
}
protected void encodeResponseData(Channel channel, ObjectOutput out, Object data)
throws IOException {
encodeResponseData(out, data);
}
}
protected void encodeResponse(Channel channel, ChannelBuffer buffer, Response res)
throws IOException {
try {
Serialization serialization = getSerialization(channel);
// header.
byte[] header = new byte[HEADER_LENGTH];
// set magic number.
Bytes.short2bytes(MAGIC, header);
// set request and serialization flag.
header[2] = serialization.getContentTypeId();
if (res.isHeartbeat()) header[2] |= FLAG_EVENT;
// set response status.
byte status = res.getStatus();
header[3] = status;
// set request id.
Bytes.long2bytes(res.getId(), header, 4);
int savedWriteIndex = buffer.writerIndex();
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH);
ChannelBufferOutputStream bos = new ChannelBufferOutputStream(buffer);
ObjectOutput out = serialization.serialize(channel.getUrl(), bos);
try {
// encode response data or error message.
if (status == Response.OK) {
if (res.isHeartbeat()) {
encodeHeartbeatData(channel, out, res.getResult());
} else {
encodeResponseData(channel, out, res.getResult());
}
} else out.writeUTF(res.getErrorMessage());
out.flushBuffer();
} finally {
// modified by lishen
if (out instanceof Cleanable) {
((Cleanable) out).cleanup();
}
}
bos.flush();
bos.close();
int len = bos.writtenBytes();
checkPayload(channel, len);
Bytes.int2bytes(len, header, 12);
// write
buffer.writerIndex(savedWriteIndex);
buffer.writeBytes(header); // write header.
buffer.writerIndex(savedWriteIndex + HEADER_LENGTH + len);
} catch (Throwable t) {
// 发送失败信息给Consumer，否则Consumer只能等超时了
if (!res.isEvent() && res.getStatus() != Response.BAD_RESPONSE) {
try {
// FIXME 在Codec中打印出错日志？在IoHanndler的caught中统一处理？
logger.warn(
"Fail to encode response: "
+ res
+ ", send bad_response info instead, cause: "
+ t.getMessage(),
t);
Response r = new Response(res.getId(), res.getVersion());
r.setStatus(Response.BAD_RESPONSE);
r.setErrorMessage(
"Failed to send response: " + res + ", cause: " + StringUtils.toString(t));
channel.send(r);
return;
} catch (RemotingException e) {
logger.warn(
"Failed to send bad_response info back: " + res + ", cause: " + e.getMessage(), e);
}
}
// 重新抛出收到的异常
if (t instanceof IOException) {
throw (IOException) t;
} else if (t instanceof RuntimeException) {
throw (RuntimeException) t;
} else if (t instanceof Error) {
throw (Error) t;
} else {
throw new RuntimeException(t.getMessage(), t);
}
}
}
@Override
protected void decode(ChannelHandlerContext ctx, ByteBuf input, List<Object> out)
throws Exception {
int readable = input.readableBytes();
if (readable <= 0) {
return;
}
int off, limit;
byte[] buf = mBuffer;
if (buf == null) {
buf = new byte[bufferSize];
off = limit = 0;
} else {
off = mOffset;
limit = mLimit;
}
com.antrou.dubbo.remoting.netty4.NettyChannel channel =
com.antrou.dubbo.remoting.netty4.NettyChannel.getOrAddChannel(
ctx.channel(), url, handler);
boolean remaining = true;
Object msg;
UnsafeByteArrayInputStream bis;
try {
do {
// read data into buffer.
int read = Math.min(readable, buf.length - limit);
input.readBytes(buf, limit, read);
limit += read;
readable -= read;
bis = new UnsafeByteArrayInputStream(buf, off, limit - off);
// decode object.
do {
try {
msg = codec.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); // adjust buffer.
off = 0;
limit = len;
}
break;
} else {
int pos = bis.position();
if (off == pos) {
remaining = false;
throw new IOException("Decode without read data.");
}
if (msg != null) {
out.add(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;
}
mBuffer = buf;
mOffset = off;
mLimit = limit;
} else {
mBuffer = null;
mOffset = mLimit = 0;
}
com.antrou.dubbo.remoting.netty4.NettyChannel.removeChannelIfDisconnected(ctx.channel());
}
}
