/* Copyright 2009 Google Inc.
*
* 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.
*
* $Id: OutputStreamConnector.java 486 2009-10-12 21:00:48Z matt.proud $
*/
package com.google.dataconnector.protocol;
import com.google.common.base.Preconditions;
import com.google.dataconnector.protocol.proto.SdcFrame.SocketDataInfo;
import com.google.inject.Inject;
import org.apache.log4j.Logger;
import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.BlockingQueue;
/**
* Converts {@link SocketDataInfo} into bytes on an output stream for use with streaming
* sockets over the SDC Frame Protocol. A queue is watched to wait for SocketDataInfo protocol
* buffers and when one is received, {@link OutputStreamConnector} writes its segment contents
* onto the wire. If a CLOSE SocketDataInfo is received, the underlying output stream is closed
* and the {@link ConnectorStateCallback#close(int)} is fired.
*
* @author rayc@google.com (Ray Colline)
*
*/
public class OutputStreamConnector extends Thread {
private static final Logger LOG = Logger.getLogger(OutputStreamConnector.class);
// runtime dependencies
private OutputStream outputStream;
private long connectionId;
private ConnectorStateCallback connectorStateCallback;
// local fields
private final BlockingQueue<SocketDataInfo> queue;
@Inject
public OutputStreamConnector(final BlockingQueue<SocketDataInfo> queue) {
this.queue = queue;
}
/**
* Watches the {@link SocketDataInfo} queue and writes any available frames to the output stream.
* If the {@link SocketDataInfo} indicates CLOSE, the output stream is closed and the
* {@link ConnectorStateCallback#close} is fired.
*/
@Override
public void run() {
Preconditions.checkNotNull(outputStream, "must set outputStream before calling start()");
Preconditions.checkNotNull(connectionId, "must set connectionId before calling start()");
try {
while (true) {
final SocketDataInfo socketDataInfo = queue.take();
if (socketDataInfo.getState() == SocketDataInfo.State.CLOSE) {
LOG.debug("Closing connection " + connectionId);
outputStream.close();
break;
} else if (socketDataInfo.getState() == SocketDataInfo.State.CONTINUE) {
LOG.debug("frame = " + socketDataInfo.toString());
outputStream.write(socketDataInfo.getSegment().toByteArray());
}
}
} catch (InterruptedException e) {
LOG.info("Interrupted while waiting for socket data frames");
} catch (IOException e) {
// TODO(rayc) Later on do something more intelligent such as reject this request not kill
// the tunnel.
LOG.debug("IO error", e);
} finally {
connectorStateCallback.close(connectionId);
LOG.debug("Stopping output for ID:" + connectionId + "active thread count:" +
Thread.activeCount());
}
}
public void setOutputStream(final OutputStream outputStream) {
this.outputStream = outputStream;
}
public void setConnectionId(final long connectionId) {
this.connectionId = connectionId;
}
public BlockingQueue<SocketDataInfo> getQueue() {
return queue;
}
public void setConnectorStateCallback(final ConnectorStateCallback connectorStateCallback) {
this.connectorStateCallback = connectorStateCallback;
}
}