下面2张图来自:http://www.open-open.com/doc/view/2e0a82e0081d489dace301a2c512053c
关于Zookeeper服务安装,配置,启动, 客户端操作参见:
http://aiilive.blog.运维网.com/1925756/1684451
http://aiilive.blog.运维网.com/1925756/1684145
1.利用Zookeeper的znode数据版本生成序列号
利用zkClient封装包操作实现:
//提前创建好存储Seq的"/createSeq"结点 CreateMode.PERSISTENT
public static final String SEQ_ZNODE = "/seq"
//通过znode数据版本实现分布式seq生成
public static class Task1 implements Runnable {
private final String taskName;
public Task1(String taskName) {
this.taskName = taskName;
}
@Override
public void run() {
ZkClient zkClient = new ZkClient("192.168.88.153:2181", 3000, 1000);
Stat stat = zkClient.writeData(SEQ_ZNODE, new byte[0], -1);
int versionAsSeq = stat.getVersion();
System.out.println(taskName + " obtain seq=" + versionAsSeq);
zkClient.close();
}
}
//main
final ExecutorService service = Executors.newFixedThreadPool(20);
for (int i = 0; i < 20; i++) {
service.execute(new Task1("[Concurrent-" + i + "]"));
}
2.利用临时带序列号的znode实现和分布式锁持久化znode实现
2.1 下图是利用分布式锁持久化znode实现
客户端采用apache curator 框架,代码:https://code.csdn.net/snippets/929300
2.2利用临时带序列号的znode实现
客户端采用:zkClient (https://github.com/adyliu/zkclient)
//提前创建好锁对象的结点"/lock" CreateMode.PERSISTENT
public static final String LOCK_ZNODE = "/lock";
//分布式锁实现分布式seq生成
public static class Task2 implements Runnable, IZkChildListener {
private final String taskName;
private final ZkClient zkClient;
private final String lockPrefix = "/loc";
private final String selfZnode;
public Task2(String taskName) {
this.taskName = taskName;
zkClient = new ZkClient("192.168.88.153:2181", 30000, 10000);
selfZnode = zkClient.createEphemeralSequential(LOCK_ZNODE + lockPrefix, new byte[0]);
}
@Override
public void run() {
zkClient.subscribeChildChanges(LOCK_ZNODE, this);
do {
} while (zkClient.isConnected());
}
private void createSeq() {
Stat stat = new Stat();
byte[] oldData = zkClient.readData(LOCK_ZNODE, stat);
byte[] newData = update(oldData);
zkClient.writeData(LOCK_ZNODE, newData);
System.out.println(taskName + selfZnode + " obtain seq=" + new String(newData));
}
private byte[] update(byte[] currentData) {
String s = new String(currentData);
int d = Integer.parseInt(s);
d = d + 1;
s = String.valueOf(d);
return s.getBytes();
}
@Override
public void handleChildChange(String parentPath, List currentChildren) throws Exception {
String[] childrensZnode = currentChildren.toArray(new String[currentChildren.size()]);
Arrays.sort(childrensZnode);
String minZnode = LOCK_ZNODE + "/" + childrensZnode[0];
if (selfZnode.equals(minZnode)) {
createSeq();
zkClient.unsubscribeChildChanges(LOCK_ZNODE, this);
zkClient.delete(selfZnode);
zkClient.close();
}
}
}
完整代码参见:https://code.csdn.net/snippets/929320
运维网声明
1、欢迎大家加入本站运维交流群:群②:261659950 群⑤:202807635 群⑦870801961 群⑧679858003
2、本站所有主题由该帖子作者发表,该帖子作者与运维网 享有帖子相关版权
3、所有作品的著作权均归原作者享有,请您和我们一样尊重他人的著作权等合法权益。如果您对作品感到满意,请购买正版
4、禁止制作、复制、发布和传播具有反动、淫秽、色情、暴力、凶杀等内容的信息,一经发现立即删除。若您因此触犯法律,一切后果自负,我们对此不承担任何责任
5、所有资源均系网友上传或者通过网络收集,我们仅提供一个展示、介绍、观摩学习的平台,我们不对其内容的准确性、可靠性、正当性、安全性、合法性等负责,亦不承担任何法律责任
6、所有作品仅供您个人学习、研究或欣赏,不得用于商业或者其他用途,否则,一切后果均由您自己承担,我们对此不承担任何法律责任
7、如涉及侵犯版权等问题,请您及时通知我们,我们将立即采取措施予以解决
8、联系人Email:admin@iyunv.com 网址:www.yunweiku.com