/apache-tomcat-6.0.35-src/java/org/apache/catalina/tribes/transport/bio/BioReplicationTask.java
Java | 166 lines | 89 code | 20 blank | 57 comment | 13 complexity | 7e06661b38dd1ca708d95b80f157972a MD5 | raw file
Possible License(s): Apache-2.0, CPL-1.0
- /*
- * 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.catalina.tribes.transport.bio;
- import org.apache.catalina.tribes.io.ObjectReader;
- import org.apache.catalina.tribes.transport.Constants;
- import org.apache.catalina.tribes.transport.AbstractRxTask;
- import java.net.Socket;
- import java.io.InputStream;
- import java.io.OutputStream;
- import org.apache.catalina.tribes.io.ListenCallback;
- import org.apache.catalina.tribes.ChannelMessage;
- import org.apache.catalina.tribes.io.ChannelData;
- import org.apache.catalina.tribes.io.BufferPool;
- /**
- * A worker thread class which can drain channels and echo-back the input. Each
- * instance is constructed with a reference to the owning thread pool object.
- * When started, the thread loops forever waiting to be awakened to service the
- * channel associated with a SelectionKey object. The worker is tasked by
- * calling its serviceChannel() method with a SelectionKey object. The
- * serviceChannel() method stores the key reference in the thread object then
- * calls notify() to wake it up. When the channel has been drained, the worker
- * thread returns itself to its parent pool.
- *
- * @author Filip Hanik
- *
- * @version $Id: BioReplicationTask.java 939515 2010-04-29 23:59:49Z kkolinko $
- */
- public class BioReplicationTask extends AbstractRxTask {
- protected static org.apache.juli.logging.Log log = org.apache.juli.logging.LogFactory.getLog( BioReplicationTask.class );
-
- protected Socket socket;
- protected ObjectReader reader;
-
- public BioReplicationTask (ListenCallback callback) {
- super(callback);
- }
- // loop forever waiting for work to do
- public synchronized void run()
- {
- if ( socket == null ) return;
- try {
- drainSocket();
- } catch ( Exception x ) {
- log.error("Unable to service bio socket");
- }finally {
- try {socket.close();}catch ( Exception ignore){}
- try {reader.close();}catch ( Exception ignore){}
- reader = null;
- socket = null;
- }
- // done, ready for more, return to pool
- if ( getTaskPool() != null ) getTaskPool().returnWorker (this);
- }
-
- public synchronized void serviceSocket(Socket socket, ObjectReader reader) {
- this.socket = socket;
- this.reader = reader;
- this.notify(); // awaken the thread
- }
-
- protected void execute(ObjectReader reader) throws Exception{
- int pkgcnt = reader.count();
- if ( pkgcnt > 0 ) {
- ChannelMessage[] msgs = reader.execute();
- for ( int i=0; i<msgs.length; i++ ) {
- /**
- * Use send ack here if you want to ack the request to the remote
- * server before completing the request
- * This is considered an asynchronized request
- */
- if (ChannelData.sendAckAsync(msgs[i].getOptions())) sendAck(Constants.ACK_COMMAND);
- try {
- //process the message
- getCallback().messageDataReceived(msgs[i]);
- /**
- * Use send ack here if you want the request to complete on this
- * server before sending the ack to the remote server
- * This is considered a synchronized request
- */
- if (ChannelData.sendAckSync(msgs[i].getOptions())) sendAck(Constants.ACK_COMMAND);
- }catch ( Exception x ) {
- if (ChannelData.sendAckSync(msgs[i].getOptions())) sendAck(Constants.FAIL_ACK_COMMAND);
- log.error("Error thrown from messageDataReceived.",x);
- }
- if ( getUseBufferPool() ) {
- BufferPool.getBufferPool().returnBuffer(msgs[i].getMessage());
- msgs[i].setMessage(null);
- }
- }
- }
-
- }
- /**
- * The actual code which drains the channel associated with
- * the given key. This method assumes the key has been
- * modified prior to invocation to turn off selection
- * interest in OP_READ. When this method completes it
- * re-enables OP_READ and calls wakeup() on the selector
- * so the selector will resume watching this channel.
- */
- protected void drainSocket () throws Exception {
- InputStream in = socket.getInputStream();
- // loop while data available, channel is non-blocking
- byte[] buf = new byte[1024];
- int length = in.read(buf);
- while ( length >= 0 ) {
- int count = reader.append(buf,0,length,true);
- if ( count > 0 ) execute(reader);
- length = in.read(buf);
- }
- }
- /**
- * send a reply-acknowledgement (6,2,3)
- * @param key
- * @param channel
- */
- protected void sendAck(byte[] command) {
- try {
- OutputStream out = socket.getOutputStream();
- out.write(command);
- out.flush();
- if (log.isTraceEnabled()) {
- log.trace("ACK sent to " + socket.getPort());
- }
- } catch ( java.io.IOException x ) {
- log.warn("Unable to send ACK back through channel, channel disconnected?: "+x.getMessage());
- }
- }
-
- public void close() {
- setDoRun(false);
- try {socket.close();}catch ( Exception ignore){}
- try {reader.close();}catch ( Exception ignore){}
- reader = null;
- socket = null;
- super.close();
- }
- }