Zookeeper the actual combat configuration service

Zookeeper The actual combat configuration service

The recent collation of information found two years ago I wrote some examples of zookeeper, today sorted out, put here, perhaps later. Server is used to start a zookeeper service.

Package my.zookeeperstudy.config;

Import org.apache.zookeeper.server.ServerCnxnFactory;
Import Org.apache.zookeeper.server.ZooKeeperServer;

Import Java.io.File;
Import java.net.InetSocketAddress;

public class Server {public

    static void Main (string[] args) throws Exception {
        int ticktime =;
        int maxclientcnxns =;
        File dir = new file (System.getproperty ("Java.io.tmpdir"), "Zookeeper"). Getabsolutefile ();
        Zookeeperserver zkserver = new Zookeeperserver (dir, dir, ticktime);
        Servercnxnfactory standaloneserverfactory = servercnxnfactory.createfactory (new inetsocketaddress (2181), MAXCLIENTCNXNS);
        Standaloneserverfactory.startup (Zkserver);
    }

Config configuration class, which contains the configuration items and methods to be manipulated, and so on.

Package my.zookeeperstudy.config;

Import org.apache.zookeeper.*;
Import java.io.IOException;
Import java.util.Collections;

Import java.util.List;

    public class Config implements watcher {private Zookeeper ZK;

    Private String BasePath = "/config"; Public Config () {} public void Connect (String hosts) throws IOException, Keeperexception, interruptedexception
        {This.zk = new Zookeeper (hosts, 1000, this); if (Zk.exists (basepath, this) = null) {zk.create (basepath, NULL, ZooDefs.Ids.OPEN_ACL_UNSAFE, Createmode.per
        Sistent); } public void set (string key, String value) throws Interruptedexception, Keeperexception {string path
        = BasePath + "/" + key; if (zk.exists (path, this) = = null) {zk.create (path, value.getbytes (), ZooDefs.Ids.OPEN_ACL_UNSAFE, Createmode .
        Persistent);
        else {zk.setdata (path, value.getbytes (),-1); } public string get (string key) thRows Interruptedexception, keeperexception {String path = BasePath + "/" + key;
            if (zk.exists (path, this)!= null) {byte[] data = zk.getdata (path, this, null);
        return new String (data);
    return null; public void Printconfig () throws Interruptedexception, keeperexception {System.out.println ("-----Begin-
        ---");
        list<string> children = Zk.getchildren (BasePath, false);
        Collections.sort (children);
        for (String Child:children) {System.out.println [child + ': ' + Get (child)];
    } System.out.println ("-----End-----"); public void Clear () throws Keeperexception, interruptedexception {if (Zk.exists (BasePath, false)!= null)
            {list<string> children = Zk.getchildren (BasePath, false);
                for (String Child:children) {zk.delete (BasePath + "/" + Child,-1); System.out.println ("Deleted"+ BasePath +"/"+ child";
        } zk.delete (BasePath,-1);
        } @Override public void process (Watchedevent event) {System.out.println ("event:" + event);
                if (event.gettype () = = Event.EventType.NodeDataChanged | |
            Event.gettype () = = Event.EventType.NodeChildrenChanged) {try {printconfig ();
            catch (Interruptedexception e) {e.printstacktrace ();
            catch (Keeperexception e) {e.printstacktrace ();
 }
        }
    }
}

Clienta and CLIENTB-two clients, analog configuration modification and synchronization

Clienta.java

Package my.zookeeperstudy.config;

public class Clienta {public
    static void Main (string[] args) throws Exception {
        config config = new Config (); 
  
   config.connect ("localhost:2181");

        while (true) {
            thread.sleep (1000);
            Config.get ("MyKey");}}


  

Clientb.java

Package my.zookeeperstudy.config;

public class ClientB {public
    static void Main (string[] args) throws Exception {
        config config = new Config (); 
  config.connect ("localhost:2181");

        for (int i = 0; I < 10000 i++) {
            config.set ("MyKey", "myvalue_" + i);
            Thread.Sleep (5 * 1000);
        }

        Config.clear ();
    }

Test
Start the server class first, then start Clienta and CLIENTB, and then observe the output of Clienta and CLIENTB.

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This article link: http://blog.csdn.net/kongxx/article/details/51457636