ZK Rob the Lord

Package com.autonavi.tinfo.t1.traffic.pub.openlr.util;

Import java.util.Collections;
Import java.util.List;
Import java.util.concurrent.Executors;
Import Java.util.concurrent.ScheduledExecutorService;
Import Java.util.concurrent.TimeUnit;
Import Java.util.concurrent.locks.Lock;
Import Java.util.concurrent.locks.ReentrantLock;

Import Org.apache.zookeeper.Watcher.Event.KeeperState;
Import Org.slf4j.Logger;
Import Org.slf4j.LoggerFactory;

Import Com.github.zkclient.IZkChildListener;
Import Com.github.zkclient.IZkStateListener;
Import com.github.zkclient.ZkClient;

public class Statusmonitor {

Private lock lock = new Reentrantlock ();//Lock Object
Private Boolean Usingha = true;
Private volatile Boolean isleader = false;

private static final Logger Logger = Loggerfactory.getlogger (Statusmonitor.class);
Timeout period
private int zksessiontimeout=5000;
private int zkconnectiontimeout=5000;
private int session_timeout = 5000;
private int connection_timeout = 5000;

Zookeeper Server List
Private String zkserverlist = "10.17.132.71:2181";

Private String Zkserverdir = "Fast-update";
Private String subnode = "OPENLR";

Child nodes created by the current client
Private String Curpath;
Private Zkclient zkclient;
Scheduledexecutorservice intervalmonitorexecutor = Executors.newsinglethreadscheduledexecutor ();

/**
* Connection Zookeeper
*/
public void init () {
Logger.info ("Statusmonitor.init zksessiontimeout:{},zkconnectiontimeout:{}", Zksessiontimeout, Zkconnectiontimeout);
try {
Connect ();
} catch (Exception e) {
This.isleader = false;
Logger.error (E.getmessage (), E);
try {
Connect ();
} catch (Exception E1) {
TODO auto-generated Catch block
E1.printstacktrace ();
Logger.error ("error occurs during sync data from ZK");
System.exit (0);
} finally {
;
}
}

Intervalmonitorexecutor.scheduleatfixedrate (New Runnable () {

@Override
public void Run () {
Lock.lock ();
try {
if (zkclient = = null) {
Isleader = false;
Return
}
if (zkclient! = null && zkclient.getzookeeper () = = null) {
Isleader = false;
Return
}
if (zkclient! = null && (!zkclient.getzookeeper (). GetState (). IsAlive ()
|| !zkclient.getzookeeper (). GetState (). isconnected ())) {
Isleader = false;
Return
}
} finally {
Lock.unlock ();
}
}
}, 0, 2, timeunit.seconds);

}

public void Connect () throws Exception {
if (!usingha) {
Return
}

if (this.zkclient! = null) {
This.zkClient.close ();
}
This.zkclient = new Zkclient (zkserverlist, Zksessiontimeout, zkconnectiontimeout);

if (!zkclient.exists ("/" + Zkserverdir)) {
Zkclient.createpersistent ("/" + Zkserverdir, NULL);
}
if (Curpath = = null) {
Curpath = Zkclient.createephemeralsequential ("/" + Zkserverdir + "/" + subnode, "Monitor". GetBytes ());
}

try {
Startwatchingtopicstatus ();
} catch (Exception e) {
TODO auto-generated Catch block
Logger.error (E.getmessage (), E);
Logger.error ("error occurs during sync data from ZK");
System.exit (0);
}
Thread.Sleep (2000);//* *
Handlemonitornodechange ();
}

public void Startwatchingtopicstatus () {
Zktopicstatuslistener Topiceventlistener = new Zktopicstatuslistener ();
Zkconnectedstatuslistener Connectedstatuslistener = new Zkconnectedstatuslistener ();
try {
Zkclient.subscribechildchanges ("/" + Zkserverdir, Topiceventlistener);
Zkclient.subscribestatechanges (Connectedstatuslistener);
} catch (Exception e) {
Logger.error (E.getmessage (), E);
try {
Thread.Sleep (1000);
} catch (Interruptedexception E1) {
TODO auto-generated Catch block
E1.printstacktrace ();
}
Startwatchingtopicstatus ();
}

}

public void Stop () {
if (zkclient = = null) {
Logger.warn ("Shutdown topic event Watcher");
Return
}
Stopwatchingtopicevents ();
Zkclient.close ();
Zkclient = null;
}

private void Beleader () {
Logger.info ("This node gains lock {} and becomes leader", Curpath);
SYSTEM.OUT.PRINTLN ("This node gains lock" + Curpath + "and becomes leader");
This.isleader = true;
}

public void Setusingha (Boolean Isusingha) {
This.usingha = Isusingha;
}

public void Setzkserverdir (String zkserverdir) {
This.zkserverdir = Zkserverdir;
}

public Boolean Isusingha () {
return Usingha;
}

public Boolean Isleader () {
return isleader;
}

public void Setzkserverlist (String zkserverlist) {
This.zkserverlist = zkserverlist;
}

/*public int Getsession_timeout () {
return session_timeout;
}

public void setsession_timeout (int session_timeout) {
Session_timeout = Session_timeout;
}

public int getconnection_timeout () {
return connection_timeout;
}

public void setconnection_timeout (int connection_timeout) {
Connection_timeout = Connection_timeout;
}*/

public int getzksessiontimeout () {
return zksessiontimeout;
}

public void setzksessiontimeout (int zksessiontimeout) {
This.zksessiontimeout = Zksessiontimeout;
}

public int getzkconnectiontimeout () {
return zkconnectiontimeout;
}

public void setzkconnectiontimeout (int zkconnectiontimeout) {
This.zkconnectiontimeout = Zkconnectiontimeout;
}

public void Handlemonitornodechange () throws Exception {
This.lock.lock ();
try {
if (zkclient = = null)
Return
if (!zkclient.exists ("/" + Zkserverdir)) {
Zkclient.createpersistent ("/" + Zkserverdir, NULL);
}

Confirm if Curpath is really the smallest node in the list
List<string> childs = Zkclient.getchildren ("/" + Zkserverdir);
if (childs = = NULL | | childs.size () = = 0) {
Create child nodes
Curpath = Zkclient.createephemeralsequential ("/" + Zkserverdir + "/" + subnode, "Monitor". GetBytes ());
Childs = Zkclient.getchildren ("/" + Zkserverdir);
}
Collections.sort (Childs);

String Thisnode = curpath.substring (("/" + Zkserverdir + "/"). Length ());
int index = Childs.indexof (Thisnode);
if (Index < 0) {
Curpath = Zkclient.createephemeralsequential ("/" + Zkserverdir + "/" + subnode, "Monitor". GetBytes ());
Childs = Zkclient.getchildren ("/" + Zkserverdir);
Collections.sort (Childs);
Thisnode = Curpath.substring (("/" + Zkserverdir + "/"). Length ());
index = Childs.indexof (Thisnode);
}

if (index = = 0) {
is indeed the smallest node
Beleader ();
} else {
This.isleader = false;
}
} finally {
This.lock.unlock ();
}
}

Class Zktopicstatuslistener implements Izkchildlistener {

@Override
public void Handlechildchange (String parentpath, list<string> currentchilds) throws Exception {
Handlemonitornodechange ();
}
}

Class Zkconnectedstatuslistener implements Izkstatelistener {

@Override
public void handlestatechanged (Keeperstate state) throws Exception {
TODO auto-generated Method Stub
if (State.equals (state). syncconnected) | | State.equals (state. Connectedreadonly)) {
System.out.println ("Zookeeper start to be connected");
Handlemonitornodechange ();
}
}

@Override
public void Handlenewsession () throws Exception {
TODO auto-generated Method Stub
}

}

public static void Main (string[] args) throws Exception {
Statusmonitor statusmonitor = new Statusmonitor ();
Statusmonitor.setzkserverlist ("10.61.97.23:2181");
Statusmonitor.setusingha (TRUE);

Statusmonitor.init ();

Thread.Sleep (100000000);
}

}

ZK Rob the Lord