/*
* Created on Nov 3, 2005
* Created by Alon Rohter
* Copyright (C) 2005, 2006 Aelitis, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* AELITIS, SAS au capital de 46,603.30 euros
* 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
*
*/
package com.aelitis.azureus.core.clientmessageservice.impl;
import java.nio.channels.SocketChannel;
import java.util.*;
import org.gudy.azureus2.core3.util.*;
import com.aelitis.azureus.core.networkmanager.VirtualChannelSelector;
import com.aelitis.azureus.core.peermanager.messaging.Message;
import com.aelitis.azureus.core.peermanager.messaging.azureus.AZGenericMapPayload;
/**
*
*/
public class NonBlockingReadWriteService {
private final VirtualChannelSelector read_selector;
private final VirtualChannelSelector write_selector;
private final ArrayList connections = new ArrayList();
private final AEMonitor connections_mon = new AEMonitor( "connections" );
private final ServiceListener listener;
private final String service_name;
private volatile boolean destroyed;
private long last_timeout_check_time = 0;
private static final int TIMEOUT_CHECK_INTERVAL_MS = 10*1000; //check for timeouts every 10sec
private final int activity_timeout_period_ms;
private final int close_delay_period_ms;
public NonBlockingReadWriteService( String _service_name, int timeout, ServiceListener _listener ) {
this( _service_name, timeout, 0, _listener );
}
public NonBlockingReadWriteService( String _service_name, int timeout, int close_delay, ServiceListener _listener ) {
this.service_name = _service_name;
this.listener = _listener;
read_selector = new VirtualChannelSelector( service_name, VirtualChannelSelector.OP_READ, false );
write_selector = new VirtualChannelSelector( service_name, VirtualChannelSelector.OP_WRITE, true );
if( timeout < TIMEOUT_CHECK_INTERVAL_MS /1000 ) timeout = TIMEOUT_CHECK_INTERVAL_MS /1000;
this.activity_timeout_period_ms = timeout *1000;
close_delay_period_ms = close_delay * 1000;
AEThread select_thread = new AEThread( "[" +service_name+ "] Service Select" ) {
public void runSupport() {
while( true ) {
boolean stop_after_select = destroyed;
if ( stop_after_select ){
read_selector.destroy();
write_selector.destroy();
}
try{
read_selector.select( 50 );
write_selector.select( 50 );
}
catch( Throwable t ) {
Debug.out( "[" +service_name+ "] SelectorLoop() EXCEPTION: ", t );
}
if (stop_after_select){
break;
}
doConnectionTimeoutChecks();
// check this at the end so we have one last run through the selectors to do cancels
// before exiting
}
}
};
select_thread.setDaemon( true );
select_thread.start();
}
public void
destroy()
{
try {
connections_mon.enter();
connections.clear();
destroyed = true;
}finally{
connections_mon.exit();
}
}
public void addClientConnection( ClientConnection connection ) {
//add to active list
try { connections_mon.enter();
if ( destroyed ){
Debug.out( "connection added after destroy" );
}
connections.add( connection );
}finally {
connections_mon.exit();
}
registerForSelection( connection );
}
public void removeClientConnection( ClientConnection connection ) {
read_selector.cancel( connection.getSocketChannel() );
write_selector.cancel( connection.getSocketChannel() );
//remove from active list
try { connections_mon.enter();
connections.remove( connection );
}
finally { connections_mon.exit(); }
}
private void registerForSelection( final ClientConnection client ) {
//READS
VirtualChannelSelector.VirtualSelectorListener read_listener = new VirtualChannelSelector.VirtualSelectorListener() {
//SUCCESS
public boolean selectSuccess( VirtualChannelSelector selector, SocketChannel sc, Object attachment ) {
try{
Message[] messages = client.readMessages();
if( messages != null ) {
for( int i=0; i < messages.length; i++ ) {
AZGenericMapPayload msg = (AZGenericMapPayload)messages[i];
ClientMessage client_msg = new ClientMessage( msg.getID(), client, msg.getMapPayload(), null ); //note no handler. we let the listener attach it
listener.messageReceived( client_msg );
}
}
return( client.getLastReadMadeProgress());
}
catch( Throwable t ) {
if ( !client.isClosePending()){
System.out.println( "[" +new Date()+ "] Connection read error [" +sc.socket().getInetAddress()+ "] [" +client.getDebugString()+ "]: " +t.getMessage() );
}
listener.connectionError( client, t );
return( false );
}
}
//FAILURE
public void selectFailure( VirtualChannelSelector selector, SocketChannel sc, Object attachment, Throwable msg ) {
if ( !destroyed ){
msg.printStackTrace();
}
listener.connectionError( client, msg );
}
};
//WRITES
final VirtualChannelSelector.VirtualSelectorListener write_listener = new VirtualChannelSelector.VirtualSelectorListener() {
public boolean selectSuccess( VirtualChannelSelector selector, SocketChannel sc, Object attachment ) {
try{
boolean more_writes_needed = client.writeMessages();
if( more_writes_needed ) {
write_selector.resumeSelects( client.getSocketChannel() ); //we need to resume since write selects are auto-paused after select op
}
return( client.getLastWriteMadeProgress());
}
catch( Throwable t ) {
System.out.println( "[" +new Date()+ "] Connection write error [" +sc.socket().getInetAddress()+ "] [" +client.getDebugString()+ "]: " +t.getMessage() );
listener.connectionError( client, t );
return( false );
}
}
public void selectFailure( VirtualChannelSelector selector, SocketChannel sc, Object attachment, Throwable msg ) {
if ( !destroyed ){
msg.printStackTrace();
}
listener.connectionError( client, msg );
}
};
write_selector.register( client.getSocketChannel(), write_listener, null ); //start writing back to the connection
write_selector.pauseSelects( client.getSocketChannel() ); //wait until we've got something to send before selecting
read_selector.register( client.getSocketChannel(), read_listener, null ); //start reading from the connection
}
private void doConnectionTimeoutChecks() {
//check timeouts
long time = System.currentTimeMillis();
if( time < last_timeout_check_time || time - last_timeout_check_time > TIMEOUT_CHECK_INTERVAL_MS ) {
ArrayList timed_out = new ArrayList();
try { connections_mon.enter();
long current_time = System.currentTimeMillis();
for( int i=0; i < connections.size(); i++ ) {
ClientConnection vconn = (ClientConnection)connections.get( i );
if( current_time < vconn.getLastActivityTime() ) { //time went backwards!
vconn.resetLastActivityTime();
}
else{
if( current_time - vconn.getLastActivityTime() > activity_timeout_period_ms ||
( close_delay_period_ms > 0 &&
current_time - vconn.getLastActivityTime() > close_delay_period_ms )){
timed_out.add( vconn ); //do actual removal outside the check loop
}
}
}
}
finally { connections_mon.exit(); }
for( int i=0; i < timed_out.size(); i++ ) {
ClientConnection vconn = (ClientConnection)timed_out.get( i );
// don't change the exception text - it is used elsewhere
listener.connectionError( vconn, new Exception( "Timeout" ));
}
last_timeout_check_time = System.currentTimeMillis();
}
}
public void sendMessage( ClientMessage message ) {
ClientConnection vconn = message.getClient();
boolean still_connected;
try { connections_mon.enter();
still_connected = connections.contains( vconn );
}
finally { connections_mon.exit(); }
if( !still_connected ) {
System.out.println( "[" +new Date()+ "] Connection message send error [connection no longer connected]: " +vconn.getDebugString()+ "]" );
message.reportFailed( new Exception("No longer connected" ));
//listener.connectionError( vconn ); //no need to call this, as there is no connection to remove
return;
}
Message reply = new AZGenericMapPayload( message.getMessageID(), message.getPayload(), (byte)1 );
vconn.sendMessage( message, reply );
write_selector.resumeSelects( vconn.getSocketChannel() ); //start write selecting now that there's something to send
}
public interface ServiceListener {
public void messageReceived( ClientMessage message );
public void connectionError( ClientConnection connection, Throwable error );
}
}
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