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wget http://mirror.bit.edu.cn/apache/zookeeper/zookeeper-3.3.6/zookeeper-3.3.6.tar.gz
tar zxvf zookeeper-3.3.6.tar.gz
cd zookeeper-3.3.6
cp conf/zoo_sample.cfg conf/zoo.cfg
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bin/zkServer.sh startÂ
æµè¯æ¯å¦æ£ç¡®è¿è¡ï¼echo ruok | nc localhost 2181ï¼å¦æå¯å¨æåï¼åè¿åimok
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bin/zkCli.sh -server localhostï¼è¿æ¥å°ZooKeeperï¼å¯ä»¥æ§è¡åç§znodeæä½ã
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import java.io.IOException;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
public class ZkTest implements Watcher
{
private static final int SESSION_TIMEOUT = 5000;
private ZooKeeper zk;
private CountDownLatch connectedSignal = new CountDownLatch(1);
public void connect(String hosts) throws IOException,InterruptedException
{
zk = new ZooKeeper(hosts,SESSION_TIMEOUT,this);
connectedSignal.await();
}
@Override
public void process(WatchedEvent event)
{
if(event.getState() == KeeperState.SyncConnected)
{
connectedSignal.countDown();
}
}
//æ°å»ºè¡¨ç¤ºç»çznode
public void create(String groupName) throws KeeperException,InterruptedException
{
String path = "/" + groupName;
String createdPath = zk.create(path,null/*data*/,Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT);
System.out.println("Created " + createdPath);
}
//ç¨æ·å°æåå å
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public void join(String groupName,String memberName) throws KeeperException,InterruptedException
{
String path = "/" + groupName + "/" + memberName;
String createdPath = zk.create(path,null/*data*/,Ids.OPEN_ACL_UNSAFE,CreateMode.EPHEMERAL);
System.out.println("Joined " + createdPath);
}
//ååºç»æå
public void list(String groupName) throws KeeperException,InterruptedException
{
String path = "/" + groupName;
try
{
List<String> children = zk.getChildren(path,false);
if(children.isEmpty())
{
System.out.printf("No members in group %s\n",groupName);
System.exit(1);
}
for(String child:children)
{
System.out.println(child);
}
}
catch (KeeperException.NoNodeException e)
{
System.out.printf("No members in group %s\n",groupName);
System.exit(1);
}
}
//å é¤ä¸ä¸ªç»åå
¶æææå
public void delete(String groupName) throws KeeperException,InterruptedException
{
String path = "/" + groupName;
try
{
List<String> children = zk.getChildren(path,false);
for(String child:children)
{
zk.delete(path + "/" + child,-1);
}
zk.delete(path,-1);
}
catch (KeeperException.NoNodeException e)
{
System.out.printf("Group %s does not exist\n",groupName);
System.exit(1);
}
}
public void close() throws InterruptedException
{
zk.close();
}
public static void main(String[] args) throws Exception
{
ZkTest zkTest = new ZkTest();
zkTest.connect("192.168.211.230");
//zkTest.create("longlonggroup");
//zkTest.join("longlonggroup", "aaa");
//Thread.sleep(60000); //è¿éç¡60ç§æ¯ä¸ºäºè®©ä½ éè¿zkCli.shä¹ç±»çå·¥å
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//zkTest.list("CMS");
//zkTest.delete("longlonggroup");
zkTest.close();
}
}
éè¦å¼ç¨jarå ï¼Mavenæ¹å¼å¦ä¸ï¼
<dependency>
<groupId>org.apache.zookeeper</groupId>
<artifactId>zookeeper</artifactId>
<version>3.4.6</version>
</dependency>
Javaå¼åçé ç½®æå¡ä»£ç
import java.io.IOException;
import java.nio.charset.Charset;
import java.util.Random;
import java.util.concurrent.CountDownLatch;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;
class ConnectionWatcher implements Watcher
{
private static final int SESSION_TIMEOUT = 5000;
protected ZooKeeper zk;
private CountDownLatch connectedSignal = new CountDownLatch(1);
public void connect(String hosts) throws IOException,InterruptedException
{
zk = new ZooKeeper(hosts,SESSION_TIMEOUT,this);
connectedSignal.await();
}
@Override
public void process(WatchedEvent event)
{
if(event.getState() == KeeperState.SyncConnected)
{
connectedSignal.countDown();
}
}
public void close() throws InterruptedException
{
zk.close();
}
}
class ActiveKeyValueStore extends ConnectionWatcher
{
private static final Charset CHARSET = Charset.forName("UTF-8");
public void write(String path,String value) throws InterruptedException,KeeperException
{
Stat stat = zk.exists(path,false);
if(stat == null)
{
zk.create(path,value.getBytes(CHARSET),Ids.OPEN_ACL_UNSAFE,CreateMode.PERSISTENT);
} else {
zk.setData(path,value.getBytes(CHARSET),-1);
}
}
public String read(String path,Watcher watcher) throws InterruptedException,KeeperException
{
byte[] data = zk.getData(path,watcher,null/*stat*/);
return new String(data,CHARSET);
}
}
//éæºæ´æ°ZooKeeperä¸çå±æ§
class ConfigUpdater
{
public static final String PATH = "/configtestbypuma";
private ActiveKeyValueStore store;
private Random random = new Random();
public ConfigUpdater() throws IOException,InterruptedException
{
store = new ActiveKeyValueStore();
store.connect("localhost");
}
public void run() throws InterruptedException,KeeperException
{
String value = random.nextInt(100) + "";
store.write(PATH, value);
System.out.printf("Set %s to %s\n",PATH,value);
Thread.sleep(random.nextInt(10)*1000);
}
public static void main(String[] args) throws Exception
{
ConfigUpdater configUpdater = new ConfigUpdater();
configUpdater.run();
}
}
//è§å¯Zookeeperä¸å±æ§çæ´æ°æ
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class ConfigWatcher implements Watcher
{
private ActiveKeyValueStore store;
public ConfigWatcher() throws IOException,InterruptedException
{
store = new ActiveKeyValueStore();
store.connect("localhost");
}
public void displayConfig() throws InterruptedException,KeeperException
{
String value = store.read(ConfigUpdater.PATH, this);
System.out.printf("Read %s as %s\n",ConfigUpdater.PATH,value);
}
@Override
public void process(WatchedEvent event)
{
if(event.getType() == EventType.NodeDataChanged)
{
try
{
displayConfig();
} catch(InterruptedException e) {
System.err.println("Interrupted. Exiting.");
Thread.currentThread().interrupt();
} catch (KeeperException e)
{
System.err.printf("KeeperException: %s. Exiting. \n", e);
}
}
}
public static void main(String[] args) throws Exception
{
ConfigWatcher configWatcher = new ConfigWatcher();
configWatcher.displayConfig();
Thread.sleep(Long.MAX_VALUE);
}
}
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tickTime=2000
dataDir=/diskl/zookeeper
dataLogDir=/disk2/zookeeper
clientPort=2181
initlimit=5
syncLimit=2
server.l=zookeeperl:2888:3888
server.2=zookeeper2:2888:3888
server.3=zookeeper3:2888:3888
tickTimeï¼ä»¥æ¯«ç§ä¸ºåä½ï¼ç¨æ¥æ§å¶å¿è·³åè¶ æ¶ï¼é»è®¤æ åµè¶ æ¶çæ¶é´ä¸ºä¸¤åçtickTime
çå¬ç«¯å£ï¼2181端å£ç¨äºå®¢æ·ç«¯è¿æ¥ï¼å¯¹äºé¢å¯¼è æ¥è¯´ï¼2888端å£ç¨äºè·éè è¿æ¥ï¼3888端å£ç¨äºé¢å¯¼è é举é¶æ®µçå ¶ä»æå¡å¨è¿æ¥ãå½ä¸ä¸ªZooKeeperæå¡å¨å¯å¨æ¶ï¼å®è¯»åmyidæ件ç¨äºç¡®å®èªå·±çæå¡å¨IDï¼ç¶åéè¿è¯»åé ç½®æ件æ¥ç¡®å®åºå½å¨åªä¸ªç«¯å£è¿è¡çå¬ï¼åæ¶ç¡®å®éåä½ä¸çå ¶ä»æå¡å¨çç½ç»å°åã
å¨å¤å¶æ¨¡å¼ä¸ï¼æ两个é¢å¤ç强å¶åæ°ï¼initLimitåsyncLimitï¼ä¸¤è é½æ¯ä»¥æ»´çåæ°çåæ°è¿è¡åº¦éã
initlimit åæ°ï¼The number of ticks that the initial synchronization phase can takeï¼è®¾å®äºå 许ææè·éè ä¸é¢å¯¼è è¿è¡è¿æ¥å¹¶åæ¥çæ¶é´ãå¦æå¨è®¾å®çæ¶é´æ®µå ï¼åæ°ä»¥ä¸çè·éè æªè½å®æåæ¥ï¼é¢å¯¼è 便ä¼å®£å¸æ¾å¼é¢å¯¼å°ä½ï¼ç¶åè¿è¡å¦å¤ä¸æ¬¡é¢å¯¼è é举ãå¦æè¿ç§æ åµç»å¸¸åç(å¯ä»¥éè¿æ¥å¿ä¸çè®°å½åç°è¿ç§æ åµ) ï¼å表æ设å®çå¼å¤ªå°ã
syncLimit åæ°ï¼The number of ticks that can pass between sending a request and getting an acknowledgementï¼è®¾å®äºå 许ä¸ä¸ªè·éè ä¸é¢å¯¼è è¿è¡åæ¥çæ¶é´ãå¦æå¨è®¾å®çæ¶é´æ®µå ï¼ä¸ä¸ªè·éè æªè½å®æåæ¥ï¼å®å°ä¼èªå·±éå¯ãææå ³èå°è¿ä¸ªè·éè ç客æ·ç«¯å°è¿æ¥å°å¦ä¸ä¸ªè·éè ã
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