/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information 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 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.activemq.transport;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.Socket;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import org.apache.activemq.command.Command;
import org.apache.activemq.command.WireFormatInfo;
import org.apache.activemq.openwire.OpenWireFormat;
import org.apache.activemq.util.IOExceptionSupport;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* Negotiates the wire format with a new connection
*/
public class WireFormatNegotiator extends TransportFilter {
private static final Log LOG = LogFactory.getLog(WireFormatNegotiator.class);
private OpenWireFormat wireFormat;
private final int minimumVersion;
private long negotiateTimeout = 15000L;
private final AtomicBoolean firstStart = new AtomicBoolean(true);
private final CountDownLatch readyCountDownLatch = new CountDownLatch(1);
private final CountDownLatch wireInfoSentDownLatch = new CountDownLatch(1);
/**
* Negotiator
*
* @param next
*/
public WireFormatNegotiator(Transport next, OpenWireFormat wireFormat, int minimumVersion) {
super(next);
this.wireFormat = wireFormat;
if (minimumVersion <= 0) {
minimumVersion = 1;
}
this.minimumVersion = minimumVersion;
// Setup the initial negociation timeout to be the same as the inital max inactivity delay specified on the wireformat
// Does not make sense for us to take longer.
try {
if( wireFormat.getPreferedWireFormatInfo() !=null ) {
setNegotiateTimeout(wireFormat.getPreferedWireFormatInfo().getMaxInactivityDurationInitalDelay());
}
} catch (IOException e) {
}
}
public void start() throws Exception {
super.start();
if (firstStart.compareAndSet(true, false)) {
try {
WireFormatInfo info = wireFormat.getPreferedWireFormatInfo();
if (LOG.isDebugEnabled()) {
LOG.debug("Sending: " + info);
}
sendWireFormat(info);
} finally {
wireInfoSentDownLatch.countDown();
}
}
}
public void stop() throws Exception {
super.stop();
readyCountDownLatch.countDown();
}
public void oneway(Object command) throws IOException {
try {
if (!readyCountDownLatch.await(negotiateTimeout, TimeUnit.MILLISECONDS)) {
throw new IOException("Wire format negotiation timeout: peer did not send his wire format.");
}
} catch (InterruptedException e) {
Thread.currentThread().interrupt();
throw new InterruptedIOException();
}
super.oneway(command);
}
public void onCommand(Object o) {
Command command = (Command)o;
if (command.isWireFormatInfo()) {
WireFormatInfo info = (WireFormatInfo)command;
if (LOG.isDebugEnabled()) {
LOG.debug("Received WireFormat: " + info);
}
try {
wireInfoSentDownLatch.await();
if (LOG.isDebugEnabled()) {
LOG.debug(this + " before negotiation: " + wireFormat);
}
if (!info.isValid()) {
onException(new IOException("Remote wire format magic is invalid"));
} else if (info.getVersion() < minimumVersion) {
onException(new IOException("Remote wire format (" + info.getVersion() + ") is lower the minimum version required (" + minimumVersion + ")"));
}
wireFormat.renegotiateWireFormat(info);
Socket socket = next.narrow(Socket.class);
if (socket != null) {
socket.setTcpNoDelay(wireFormat.isTcpNoDelayEnabled());
}
if (LOG.isDebugEnabled()) {
LOG.debug(this + " after negotiation: " + wireFormat);
}
} catch (IOException e) {
onException(e);
} catch (InterruptedException e) {
onException((IOException)new InterruptedIOException().initCause(e));
} catch (Exception e) {
onException(IOExceptionSupport.create(e));
}
readyCountDownLatch.countDown();
onWireFormatNegotiated(info);
}
getTransportListener().onCommand(command);
}
public void onException(IOException error) {
readyCountDownLatch.countDown();
/*
* try { super.oneway(new ExceptionResponse(error)); } catch
* (IOException e) { // ignore as we are already throwing an exception }
*/
super.onException(error);
}
public String toString() {
return next.toString();
}
protected void sendWireFormat(WireFormatInfo info) throws IOException {
next.oneway(info);
}
protected void onWireFormatNegotiated(WireFormatInfo info) {
}
public long getNegotiateTimeout() {
return negotiateTimeout;
}
public void setNegotiateTimeout(long negotiateTimeout) {
this.negotiateTimeout = negotiateTimeout;
}
}