org.jgroups.demos.LockServiceDemo Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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package org.jgroups.demos;
import org.jgroups.JChannel;
import org.jgroups.blocks.locking.LockNotification;
import org.jgroups.blocks.locking.LockService;
import org.jgroups.jmx.JmxConfigurator;
import org.jgroups.util.Owner;
import org.jgroups.util.Util;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.Lock;
/**
* Demos the LockService
*/
public class LockServiceDemo implements LockNotification {
protected String props;
protected JChannel ch;
protected LockService lock_service;
protected String name;
public LockServiceDemo(String props, String name) {
this.props=props;
this.name=name;
}
public void start() throws Exception {
try {
ch=new JChannel(props);
if(name != null)
ch.setName(name);
lock_service=new LockService(ch);
lock_service.addLockListener(this);
ch.connect("lock-cluster");
JmxConfigurator.registerChannel(ch, Util.getMBeanServer(), "lock-service", ch.getClusterName(), true);
loop();
}
catch(Exception e) {
e.printStackTrace();
}
finally {
Util.close(ch);
}
}
public void start(JChannel ch) throws Exception {
this.ch=ch;
lock_service=new LockService(ch);
lock_service.addLockListener(this);
ch.connect("lock-cluster");
JmxConfigurator.registerChannel(ch, Util.getMBeanServer(), "lock-service", ch.getClusterName(), true);
try {
loop();
}
catch(Exception e) {
e.printStackTrace();
}
finally {
Util.close(ch);
}
}
public void lockCreated(String lock_name) {
System.out.println("server lock \"" + lock_name + "\" created");
}
public void lockDeleted(String name) {
}
public void lockRevoked(String lock_name, Owner current_owner) {
System.out.printf("\"%s\" has been revoked (existing owner is %s); releasing lock\n", lock_name, current_owner);
Lock lock=lock_service.getLock(lock_name);
lock.unlock();
}
public void locked(String lock_name, Owner owner) {
System.out.println("\"" + lock_name + "\" locked by " + owner);
}
public void unlocked(String lock_name, Owner owner) {
System.out.println("\"" + lock_name + "\" unlocked by " + owner);
}
public void awaiting(String lock_name, Owner owner) {
System.out.println("awaiting \"" + lock_name + "\" by " + owner);
}
public void awaited(String lock_name, Owner owner) {
System.out.println("awaited \"" + lock_name + "\" by " + owner);
}
protected void loop() throws Exception {
List lock_names;
while(ch.isConnected()) {
String line=Util.readStringFromStdin(": ");
if(line == null || line.startsWith("quit") || line.startsWith("exit"))
break;
if(line.startsWith("lock")) {
lock_names=parseLockNames(line.substring("lock".length()).trim());
for(String lock_name: lock_names) {
Lock lock=lock_service.getLock(lock_name);
lock.lock();
}
}
else if(line.startsWith("trylock")) {
lock_names=parseLockNames(line.substring("trylock".length()).trim());
String tmp=lock_names.get(lock_names.size() -1);
long timeout=-1;
try {
timeout=Long.parseLong(tmp);
lock_names.remove(lock_names.size() -1);
}
catch(NumberFormatException e) {
}
for(String lock_name: lock_names) {
Lock lock=lock_service.getLock(lock_name);
boolean rc;
if(timeout < 0)
rc=lock.tryLock();
else
rc=lock.tryLock(timeout, TimeUnit.MILLISECONDS);
if(!rc)
System.err.println("Failed locking \"" + lock_name + "\"");
}
}
else if(line.startsWith("multilock")) { // multilock X 10
List tokens=parseLockNames(line.substring("multilock".length()).trim());
if(tokens == null || tokens.size() != 2) {
help();
break;
}
String lock_name=tokens.get(0);
int num_iterations=Integer.valueOf(tokens.get(1));
Lock lock=lock_service.getLock(lock_name);
for(int i=0; i < num_iterations; i++) {
lock.lock();
lock.unlock();
}
}
else if(line.startsWith("unlock")) {
lock_names=parseLockNames(line.substring("unlock".length()).trim());
for(String lock_name: lock_names) {
if(lock_name.equalsIgnoreCase("all")) {
lock_service.unlockAll();
break;
}
else {
Lock lock=lock_service.getLock(lock_name);
if(lock != null)
lock.unlock();
}
}
}
else if(line.startsWith("view"))
System.out.println("View: " + ch.getView());
else if(line.startsWith("help"))
help();
printLocks();
}
}
protected static List parseLockNames(String line) {
List lock_names=new ArrayList<>();
if(line == null || line.isEmpty())
return lock_names;
StringTokenizer tokenizer=new StringTokenizer(line);
while(tokenizer.hasMoreTokens())
lock_names.add(tokenizer.nextToken());
return lock_names;
}
protected void printLocks() {
System.out.println("\n" + lock_service.printLocks());
}
public static void main(String[] args) throws Exception {
String props=null;
String name=null;
for(int i=0; i < args.length; i++) {
if(args[i].equals("-props")) {
props=args[++i];
continue;
}
if(args[i].equals("-name")) {
name=args[++i];
continue;
}
help();
return;
}
LockServiceDemo demo=new LockServiceDemo(props, name);
demo.start();
}
protected static void help() {
System.out.println("\nLockServiceDemo [-props properties] [-name name]\n" +
"Valid commands:\n\n" +
"lock ()+\n" +
"unlock ( | \"ALL\")+\n" +
"trylock ()+ []\n" +
"multilock \n");
System.out.println("Example:\nlock lock lock2 lock3\nunlock all\ntrylock bela michelle 300");
}
}