/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
*
* If applicable add the following below this CDDL HEADER,
* with the fields enclosed by brackets "[]" replaced with
* your own identifying information: Portions Copyright
* [year] [name of copyright owner]
*/
/*
* @(#)BrokerLinkWriter.java 1.11 05/02/06
*
* Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
*/
package com.sun.messaging.jmq.jmsserver.multibroker.fullyconnected;
import java.util.*;
import java.io.*;
import java.net.*;
import com.sun.messaging.jmq.util.log.Logger;
import com.sun.messaging.jmq.jmsserver.Globals;
import com.sun.messaging.jmq.jmsserver.resources.BrokerResources;
import com.sun.messaging.jmq.jmsserver.multibroker.raptor.ProtocolGlobals;
import com.sun.messaging.jmq.io.*;
/**
* This class implements a dedicated packet writer thread. Each
* BrokerLink instance has its own BrokerLinkWriter instance..
*/
class BrokerLinkWriter extends Thread {
private OutputStream os = null;
private LinkedList q = null;
private BrokerLink parent;
private BrokerAddressImpl remote = null;
private boolean flowControl = false;
private ArrayList backupQ = null;
private final int MAX_BUFFER_SIZE = 8192;
private Logger logger = Globals.getLogger();
private boolean stopThread = false;
private boolean threadInWaiting = false;
private boolean shutdownOutput = false;
private boolean writeActive = false;
public BrokerLinkWriter(BrokerAddressImpl remote, BrokerLink parent) {
this.remote = remote;
this.parent = parent;
setName("BrokerLinkWriter:" + remote);
setDaemon(true);
}
/**
* Set the output stream and start the writer thread.
*/
public void startWriterThread(OutputStream os) {
this.os = new BufferedOutputStream(os, MAX_BUFFER_SIZE);
q = new LinkedList();
flowControl = false;
backupQ = new ArrayList();
start();
}
public void setFlowControl(boolean enabled) {
synchronized (q) {
if (stopThread || this.shutdownOutput) return;
flowControl = enabled;
if (flowControl == false) {
if (! backupQ.isEmpty()) {
q.addAll(0, backupQ);
backupQ.clear();
q.notify();
}
}
}
}
/**
* Terminate the writer thread.
*/
public void shutdown() {
if (q == null) return;
synchronized (q) {
if (shutdownOutput) return;
stopThread = true;
q.notify();
}
}
public boolean isOutputShutdown() {
if (q == null) return false;
synchronized(q) {
return shutdownOutput;
}
}
/**
* Adds a packet to the queue and wakes up the writer thread.
*/
public void sendPacket(Object p, boolean shutdownOutput) throws IOException {
synchronized (q) {
if (stopThread || this.shutdownOutput) {
throw new IOException(
"Packet send failed. Unreachable BrokerAddress : " + remote);
}
if (!shutdownOutput) {
q.add(p);
q.notify();
return;
}
this.shutdownOutput = true;
while (this.isAlive() && !threadInWaiting) {
try {
q.wait();
} catch (Exception e) {/* Ignore */}
}
try {
sendPacketDirect(p);
stopThread = true;
q.notify();
parent.closeConn(true, false);
if (!parent.isOutputShutdown()) {
throw new IOException("shutdownOutput failed");
}
} catch (IOException e) {
this.shutdownOutput = false;
parent.closeConn(false, true);
throw e;
}
}
}
public void sendPacket(Object p) throws IOException {
sendPacket(p, false);
}
private void sendPacketDirect(Object p) throws IOException {
if (p instanceof GPacket) {
sendPacketDirect((GPacket)p, true);
} else {
sendPacketDirect((Packet)p, true);
}
}
/**
* Actually writes the packet to the wire.
*/
private void sendPacketDirect(GPacket gp, boolean doFlush) throws IOException {
if (os == null) throw new IOException("os null");
try {
gp.write(os);
if (doFlush) os.flush();
if (gp.getType() != ProtocolGlobals.G_PING) writeActive = true;
}
catch (IOException e) {
os = null;
throw e;
}
}
/**
* Actually writes the packet to the wire.
*/
private void sendPacketDirect(Packet p, boolean doFlush) throws IOException {
if (os == null) throw new IOException("os null");
try {
p.writePacket(os);
if (doFlush) os.flush();
if (p.getPacketType() != Packet.PING) writeActive = true;
}
catch (IOException e) {
os = null;
throw e;
}
}
protected void clearWriteActiveFlag() {
writeActive = false;
}
protected boolean isWriteActive() {
return writeActive;
}
public void run() {
ArrayList l = new ArrayList();
while (true) {
l.clear();
synchronized (q) {
while (q.isEmpty() && stopThread == false) {
try {
threadInWaiting = true;
q.notify();
q.wait();
threadInWaiting = false;
}
catch (Exception e) {}
}
if (stopThread)
return;
int n = 0;
boolean bufferFull = false;
while (! q.isEmpty()) {
Object o = q.getFirst();
GPacket gp = null;
Packet p = null;
try {
gp = (GPacket) o;
}
catch (ClassCastException cce) {
// Not a GPacket.
p = (Packet) o;
}
if (gp != null) {
if (flowControl && gp.getBit(gp.F_BIT)) {
backupQ.add(gp);
}
else {
if (n + gp.getSize() > MAX_BUFFER_SIZE) {
bufferFull = true;
break;
}
l.add(gp);
n += gp.getSize();
}
}
else {
if (flowControl && p.getFlag(p.USE_FLOW_CONTROL)) {
backupQ.add(p);
}
else {
if (n + p.getPacketSize() > MAX_BUFFER_SIZE) {
bufferFull = true;
break;
}
l.add(p);
n += p.getPacketSize();
}
}
q.removeFirst();
}
// If nothing was written because the first packet
// was too big...
if (l.size() == 0 && bufferFull && !q.isEmpty())
l.add(q.removeFirst());
}
// The following operations do the actual socket I/O,
// and must be done outside the synchronized block.
try {
for (int i = 0; i < l.size(); i++) {
try {
GPacket gp = (GPacket) l.get(i);
sendPacketDirect(gp, false);
}
catch (ClassCastException cce) {
Packet p = (Packet) l.get(i);
sendPacketDirect(p, false);
}
}
if (os != null) os.flush();
}
catch (Exception e) {
os = null;
}
}
}
}
/*
* EOF
*/
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