Tomcat example source code file (BioSender.java)

This example Tomcat source code file (BioSender.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Tomcat tags/keywords

biosender, datasender, inetsocketaddress, integer, integer, io, ioexception, ioexception, long, long, net, network, remoteprocessexception, socket, string, string, stringbuffer, util

The Tomcat BioSender.java source code

/*
 * 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 java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.util.Arrays;

import org.apache.catalina.tribes.RemoteProcessException;
import org.apache.catalina.tribes.io.XByteBuffer;
import org.apache.catalina.tribes.transport.AbstractSender;
import org.apache.catalina.tribes.transport.Constants;
import org.apache.catalina.tribes.transport.DataSender;
import org.apache.catalina.tribes.transport.SenderState;
import org.apache.catalina.tribes.util.StringManager;

/**
 * Send cluster messages with only one socket. Ack and keep Alive Handling is
 * supported
 * 
 * @author Peter Rossbach
 * @author Filip Hanik
 * @version $Revision: 532608 $ $Date: 2007-04-26 06:58:20 +0200 (jeu., 26 avr. 2007) $
 * @since 5.5.16
 */
public class BioSender extends AbstractSender implements DataSender {

    private static org.apache.juli.logging.Log log = org.apache.juli.logging.LogFactory.getLog(BioSender.class);

    /**
     * The string manager for this package.
     */
    protected static StringManager sm = StringManager.getManager(Constants.Package);

    // ----------------------------------------------------- Instance Variables

    /**
     * The descriptive information about this implementation.
     */
    private static final String info = "DataSender/3.0";

    
    /**
     * current sender socket
     */
    private Socket socket = null;
    private OutputStream soOut = null;
    private InputStream soIn = null;
    
    protected XByteBuffer ackbuf = new XByteBuffer(Constants.ACK_COMMAND.length,true);


    // ------------------------------------------------------------- Constructor
    
    public BioSender()  {
    }


    // ------------------------------------------------------------- Properties

    /**
     * Return descriptive information about this implementation and the
     * corresponding version number, in the format
     * <code><description>/<version>.
     */
    public String getInfo() {
        return (info);
    }

    // --------------------------------------------------------- Public Methods

    /**
     * Connect other cluster member receiver 
     * @see org.apache.catalina.tribes.transport.IDataSender#connect()
     */
    public  void connect() throws IOException {
        openSocket();
   }

 
    /**
     * disconnect and close socket
     * 
     * @see IDataSender#disconnect()
     */
    public  void disconnect() {
        boolean connect = isConnected();
        closeSocket();
        if (connect) {
            if (log.isDebugEnabled())
                log.debug(sm.getString("IDataSender.disconnect", getAddress().getHostAddress(), new Integer(getPort()), new Long(0)));
        }
        
    }

    /**
     * Send message
     * 
     * @see org.apache.catalina.tribes.transport.IDataSender#sendMessage(,
     *      ChannelMessage)
     */
    public  void sendMessage(byte[] data, boolean waitForAck) throws IOException {
        IOException exception = null;
        setAttempt(0);
        try {
             // first try with existing connection
             pushMessage(data,false,waitForAck);
        } catch (IOException x) {
            SenderState.getSenderState(getDestination()).setSuspect();
            exception = x;
            if (log.isTraceEnabled()) log.trace(sm.getString("IDataSender.send.again", getAddress().getHostAddress(),new Integer(getPort())),x);
            while ( getAttempt()<getMaxRetryAttempts() ) {
                try {
                    setAttempt(getAttempt()+1);
                    // second try with fresh connection
                    pushMessage(data, true,waitForAck);
                    exception = null;
                } catch (IOException xx) {
                    exception = xx;
                    closeSocket();
                }
            }
        } finally {
            setRequestCount(getRequestCount()+1);
            keepalive();
            if ( exception != null ) throw exception;
        }
    }

    
    /**
     * Name of this SockerSender
     */
    public String toString() {
        StringBuffer buf = new StringBuffer("DataSender[(");
        buf.append(super.toString()).append(")");
        buf.append(getAddress()).append(":").append(getPort()).append("]");
        return buf.toString();
    }

    // --------------------------------------------------------- Protected Methods
 
    /**
     * open real socket and set time out when waitForAck is enabled
     * is socket open return directly
     */
    protected void openSocket() throws IOException {
       if(isConnected()) return ;
       try {
           socket = new Socket();
           InetSocketAddress sockaddr = new InetSocketAddress(getAddress(), getPort());
           socket.connect(sockaddr,(int)getTimeout());
           socket.setSendBufferSize(getTxBufSize());
           socket.setReceiveBufferSize(getRxBufSize());
           socket.setSoTimeout( (int) getTimeout());
           socket.setTcpNoDelay(getTcpNoDelay());
           socket.setKeepAlive(getSoKeepAlive());
           socket.setReuseAddress(getSoReuseAddress());
           socket.setOOBInline(getOoBInline());
           socket.setSoLinger(getSoLingerOn(),getSoLingerTime());
           socket.setTrafficClass(getSoTrafficClass());
           setConnected(true);
           soOut = socket.getOutputStream();
           soIn  = socket.getInputStream();
           setRequestCount(0);
           setConnectTime(System.currentTimeMillis());
           if (log.isDebugEnabled())
               log.debug(sm.getString("IDataSender.openSocket", getAddress().getHostAddress(), new Integer(getPort()), new Long(0)));
      } catch (IOException ex1) {
          SenderState.getSenderState(getDestination()).setSuspect();
          if (log.isDebugEnabled())
              log.debug(sm.getString("IDataSender.openSocket.failure",getAddress().getHostAddress(), new Integer(getPort()),new Long(0)), ex1);
          throw (ex1);
        }
        
     }

    /**
     * close socket
     * 
     * @see DataSender#disconnect()
     * @see DataSender#closeSocket()
     */
    protected void closeSocket() {
        if(isConnected()) {
             if (socket != null) {
                try {
                    socket.close();
                } catch (IOException x) {
                } finally {
                    socket = null;
                    soOut = null;
                    soIn = null;
                }
            }
            setRequestCount(0);
            setConnected(false);
            if (log.isDebugEnabled())
                log.debug(sm.getString("IDataSender.closeSocket",getAddress().getHostAddress(), new Integer(getPort()),new Long(0)));
       }
    }

    /**
     * Push messages with only one socket at a time
     * Wait for ack is needed and make auto retry when write message is failed.
     * After sending error close and reopen socket again.
     * 
     * After successfull sending update stats
     * 
     * WARNING: Subclasses must be very carefull that only one thread call this pushMessage at once!!!
     * 
     * @see #closeSocket()
     * @see #openSocket()
     * @see #writeData(ChannelMessage)
     * 
     * @param data
     *            data to send
     * @since 5.5.10
     */
    
    protected void pushMessage(byte[] data, boolean reconnect, boolean waitForAck) throws IOException {
        keepalive();
        if ( reconnect ) closeSocket();
        if (!isConnected()) openSocket();
        soOut.write(data);
        soOut.flush();
        if (waitForAck) waitForAck();
        SenderState.getSenderState(getDestination()).setReady();

    }
    
    /**
     * Wait for Acknowledgement from other server
     * FIXME Please, not wait only for three charcters, better control that the wait ack message is correct.
     * @param timeout
     * @throws java.io.IOException
     * @throws java.net.SocketTimeoutException
     */
    protected void waitForAck() throws java.io.IOException {
        try {
            boolean ackReceived = false;
            boolean failAckReceived = false;
            ackbuf.clear();
            int bytesRead = 0;
            int i = soIn.read();
            while ((i != -1) && (bytesRead < Constants.ACK_COMMAND.length)) {
                bytesRead++;
                byte d = (byte)i;
                ackbuf.append(d);
                if (ackbuf.doesPackageExist() ) {
                    byte[] ackcmd = ackbuf.extractDataPackage(true).getBytes();
                    ackReceived = Arrays.equals(ackcmd,org.apache.catalina.tribes.transport.Constants.ACK_DATA);
                    failAckReceived = Arrays.equals(ackcmd,org.apache.catalina.tribes.transport.Constants.FAIL_ACK_DATA);
                    ackReceived = ackReceived || failAckReceived;
                    break;
                }
                i = soIn.read();
            }
            if (!ackReceived) {
                if (i == -1) throw new IOException(sm.getString("IDataSender.ack.eof",getAddress(), new Integer(socket.getLocalPort())));
                else throw new IOException(sm.getString("IDataSender.ack.wrong",getAddress(), new Integer(socket.getLocalPort())));
            } else if ( failAckReceived && getThrowOnFailedAck()) {
                throw new RemoteProcessException("Received a failed ack:org.apache.catalina.tribes.transport.Constants.FAIL_ACK_DATA");
            }
        } catch (IOException x) {
            String errmsg = sm.getString("IDataSender.ack.missing", getAddress(),new Integer(socket.getLocalPort()), new Long(getTimeout()));
            if ( SenderState.getSenderState(getDestination()).isReady() ) {
                SenderState.getSenderState(getDestination()).setSuspect();
                if ( log.isWarnEnabled() ) log.warn(errmsg, x);
            } else {
                if ( log.isDebugEnabled() )log.debug(errmsg, x);
            }
            throw x;
        } finally {
            ackbuf.clear();
        }
    }
}