zookeeper_03:Java 客户端(原生API)
- 环境配置
- 下载并ZooKeeper的发行版
- 新建Java project,并导入jar包
- 创建会话
public class CreateSession implements Watcher {
private static ZooKeeper zookeeper;
public static void main(String[] args) throws IOException, InterruptedException {
zookeeper = new ZooKeeper("192.168.1.105:2181",5000,new CreateSession());
System.out.println(zookeeper.getState());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(){
System.out.println("do something");
}
public void process(WatchedEvent event) {
System.out.println("收到事件:"+event);
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething();
}
}
}
}
- 同步创建节点
public class CreateNodeSync implements Watcher {
private static ZooKeeper zookeeper;
public static void main(String[] args) throws IOException, InterruptedException {
zookeeper = new ZooKeeper("192.168.124.128:2181,192.168.124.128:2182,192.168.124.128:2183",5000,new CreateNodeSync());
System.out.println(zookeeper.getState());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(){
try {
String path = zookeeper.create("/test", "test".getBytes(), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
System.out.println("return path:"+path);
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println("do something");
}
public void process(WatchedEvent event) {
System.out.println("收到事件:"+event);
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething();
}
}
}
}
- 异步创建节点
import java.io.IOException;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
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.Perms;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Id;
import org.apache.zookeeper.server.auth.DigestAuthenticationProvider;
public class CreateNodeSyncAuth implements Watcher {
private static ZooKeeper zookeeper;
private static boolean somethingDone = false;
public static void main(String[] args) throws IOException, InterruptedException {
zookeeper = new ZooKeeper("192.168.124.128:2181,192.168.124.128:2182,192.168.124.128:2183",5000,new CreateNodeSyncAuth());
System.out.println(zookeeper.getState());
Thread.sleep(Integer.MAX_VALUE);
}
/*
* 权限模式(scheme): ip, digest
* 授权对象(ID)
* ip权限模式: 具体的ip地址
* digest权限模式: username:Base64(SHA-1(username:password))
* 权限(permission): create(C), DELETE(D),READ(R), WRITE(W), ADMIN(A)
* 注:单个权限,完全权限,复合权限
*
* 权限组合: scheme + ID + permission
*
*
*
* */
private void doSomething(){
try {
ACL aclIp = new ACL(Perms.READ,new Id("ip","192.168.124.128"));
ACL aclDigest = new ACL(Perms.READ|Perms.WRITE,new Id("digest",DigestAuthenticationProvider.generateDigest("zhangsan:123456")));
ArrayList<ACL> acls = new ArrayList<ACL>();
acls.add(aclDigest);
acls.add(aclIp);
//zookeeper.addAuthInfo("digest", "zhangsan:123456".getBytes());
String path = zookeeper.create("/test", "test".getBytes(), acls, CreateMode.PERSISTENT);
System.out.println("return path:"+path);
somethingDone = true;
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void process(WatchedEvent event) {
System.out.println("收到事件:"+event);
if (event.getState()==KeeperState.SyncConnected){
if (!somethingDone && event.getType()==EventType.None && null==event.getPath()){
doSomething();
}
}
}
}
StringCallback{
public void (int rc,String path,Object ctx,String name)
}
rc是result code 服务端响应结果码。客户端可以从这个结果码中识别出API的调用结果,常见的结果码有:
0(OK),接口调用成功
-4(ConnectionLoss),客户端和服务器连接断开
-110(NodeExists) 节点已存在
-112(SessionExpired)会话已过期
path: 接口调用传入的数据节点的节点路径
ctx: 接口调用传入的ctx参数
name: 实际在服务器端创建的节点名
- 同步删除节点
import java.io.IOException;
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.ZooKeeper;
public class DeleteNodeSync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new DeleteNodeSync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zooKeeper){
try {
zooKeeper.delete("/node_7", -1);
} catch (InterruptedException e) {
e.printStackTrace();
} catch (KeeperException e) {
e.printStackTrace();
}
}
@Override
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}
}
}
}
- 异步删除节点
import java.io.IOException;
import org.apache.zookeeper.AsyncCallback;
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.ZooKeeper;
public class DeleteNodeASync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new DeleteNodeASync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(WatchedEvent event){
zooKeeper.delete("/node_6", -1, new IVoidCallback(),null);
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(event);
}
}
}
static class IVoidCallback implements AsyncCallback.VoidCallback{
public void processResult(int rc, String path, Object ctx) {
StringBuilder sb = new StringBuilder();
sb.append("rc="+rc).append("\n");
sb.append("path"+path).append("\n");
sb.append("ctx="+ctx).append("\n");
System.out.println(sb.toString());
}
}
}
- 同步读取节点
import java.io.IOException;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class GetDataSync implements Watcher{
private static ZooKeeper zooKeeper;
private static Stat stat = new Stat();
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new GetDataSync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zookeeper){
zookeeper.addAuthInfo("digest", "jike:123456".getBytes());
try {
System.out.println(new String(zooKeeper.getData("/node_4", true, stat)));
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
if (event.getType()==EventType.NodeDataChanged){
try {
System.out.println(new String(zooKeeper.getData(event.getPath(), true, stat)));
System.out.println("stat:"+stat);
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
}
- 异步读取节点
import java.io.IOException;
import org.apache.zookeeper.AsyncCallback;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class GetDataASync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new GetDataASync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zookeeper){
zooKeeper.getData("/node_1", true, new IDataCallback(), null);
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
if (event.getType()==EventType.NodeDataChanged){
try {
zooKeeper.getData(event.getPath(), true, new IDataCallback(), null);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
}
static class IDataCallback implements AsyncCallback.DataCallback{
public void processResult(int rc, String path, Object ctx, byte[] data,Stat stat) {
try {
System.out.println(new String(zooKeeper.getData(path, true, stat)));
System.out.println("stat:"+stat);
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
- 同步节点检测
import java.io.IOException;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class NodeExistsSync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new NodeExistsSync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zooKeeper){
try{
Stat stat = zooKeeper.exists("/node_1", true);
System.out.println(stat);
}catch(Exception e){
}
}
@Override
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
try {
if (event.getType()==EventType.NodeCreated){
System.out.println(event.getPath()+" created");
System.out.println(zooKeeper.exists(event.getPath(), true));
}
else if (event.getType()==EventType.NodeDataChanged){
System.out.println(event.getPath()+" updated");
System.out.println(zooKeeper.exists(event.getPath(), true));
}
else if (event.getType()==EventType.NodeDeleted){
System.out.println(event.getPath()+" deleted");
System.out.println(zooKeeper.exists(event.getPath(), true));
}
} catch (Exception e) {
}
}
}
}
}
- 异步检测节点
import java.io.IOException;
import org.apache.zookeeper.AsyncCallback;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class NodeExistsASync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new NodeExistsASync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zookeeper){
zooKeeper.exists("/node_1", true, new IStateCallback(), null);
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
try {
if (event.getType()==EventType.NodeCreated){
System.out.println(event.getPath()+" created");
zooKeeper.exists(event.getPath(), true, new IStateCallback(), null);
}
else if (event.getType()==EventType.NodeDataChanged){
System.out.println(event.getPath()+" updated");
zooKeeper.exists(event.getPath(), true, new IStateCallback(), null);
}
else if (event.getType()==EventType.NodeDeleted){
System.out.println(event.getPath()+" deleted");
zooKeeper.exists(event.getPath(), true, new IStateCallback(), null);
}
} catch (Exception e) {
}
}
}
}
static class IStateCallback implements AsyncCallback.StatCallback{
public void processResult(int rc, String path, Object ctx, Stat stat) {
System.out.println("rc:"+rc);
}
}
}
- 同步获取子节点
import java.io.IOException;
import java.util.List;
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.ZooKeeper;
public class GetChildrenSync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new GetChildrenSync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zooKeeper){
try {
List<String> children = zooKeeper.getChildren("/", true);
System.out.println(children);
} catch (Exception e) {
}
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
if (event.getType()==EventType.NodeChildrenChanged){
try {
System.out.println(zooKeeper.getChildren(event.getPath(), true));
} catch (KeeperException e) {
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
}
- 异步获取子节点
import java.io.IOException;
import java.util.List;
import org.apache.zookeeper.AsyncCallback;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class GetChildrenASync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new GetChildrenASync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zookeeper){
try {
zooKeeper.getChildren("/", true, new IChildren2Callback(), null);
} catch (Exception e) {
}
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}else{
if (event.getType()==EventType.NodeChildrenChanged){
zooKeeper.getChildren(event.getPath(), true, new IChildren2Callback(), null);
}
}
}
}
static class IChildren2Callback implements AsyncCallback.Children2Callback{
public void processResult(int rc, String path, Object ctx,List<String> children, Stat stat) {
StringBuilder sb = new StringBuilder();
sb.append("rc="+rc).append("\n");
sb.append("path="+path).append("\n");
sb.append("ctx="+ctx).append("\n");
sb.append("children="+children).append("\n");
sb.append("stat="+stat).append("\n");
System.out.println(sb.toString());
}
}
}
- 同步更新
import java.io.IOException;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class UpdateNodeSync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new UpdateNodeSync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(ZooKeeper zooKeeper){
try {
Stat stat = zooKeeper.setData("/node_6", "123".getBytes(), -1);
System.out.println("stat:"+stat);
} catch (InterruptedException e) {
e.printStackTrace();
} catch (KeeperException e) {
e.printStackTrace();
}
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(zooKeeper);
}
}
}
}
- 异步更新
import java.io.IOException;
import org.apache.zookeeper.AsyncCallback;
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.ZooKeeper;
import org.apache.zookeeper.data.Stat;
public class UpdateNodeASync implements Watcher{
private static ZooKeeper zooKeeper;
public static void main(String[] args) throws IOException, InterruptedException, KeeperException {
zooKeeper = new ZooKeeper("192.168.1.105:2181",5000,new UpdateNodeASync());
System.out.println(zooKeeper.getState().toString());
Thread.sleep(Integer.MAX_VALUE);
}
private void doSomething(WatchedEvent event){
zooKeeper.setData("/node_6", "234".getBytes(), -1, new IStatCallback(),null);
}
public void process(WatchedEvent event) {
if (event.getState()==KeeperState.SyncConnected){
if (event.getType()==EventType.None && null==event.getPath()){
doSomething(event);
}
}
}
static class IStatCallback implements AsyncCallback.StatCallback{
public void processResult(int rc, String path, Object ctx, Stat stat) {
StringBuilder sb = new StringBuilder();
sb.append("rc="+rc).append("\n");
sb.append("path"+path).append("\n");
sb.append("ctx="+ctx).append("\n");
sb.append("Stat="+stat).append("\n");
System.out.println(sb.toString());
}
}
}
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