Zookeeper 客戶端

環境搭建參考Zookeeper 環境搭建筆記

本地客戶端 zkCli.sh

./bin/zkCli.sh

[zk: localhost:2181(CONNECTED) 4] help
ZooKeeper -server host:port cmd args
	addauth scheme auth
	close 
	config [-c] [-w] [-s]
	connect host:port
	create [-s] [-e] [-c] [-t ttl] path [data] [acl]
	delete [-v version] path
	deleteall path
	delquota [-n|-b] path
	get [-s] [-w] path
	getAcl [-s] path
	history 
	listquota path
	ls [-s] [-w] [-R] path
	ls2 path [watch]
	printwatches on|off
	quit 
	reconfig [-s] [-v version] [[-file path] | [-members serverID=host:port1:port2;port3[,...]*]] | [-add serverId=host:port1:port2;port3[,...]]* [-remove serverId[,...]*]
	redo cmdno
	removewatches path [-c|-d|-a] [-l]
	rmr path
	set [-s] [-v version] path data
	setAcl [-s] [-v version] [-R] path acl
	setquota -n|-b val path
	stat [-w] path
	sync path
Command not found: Command not found help

---

ls /

不能直接遞歸創建路徑

create /v1/v2 v
Node does not exist: /v1/v2
需要一級一級創建

create /v1 v
create /v1/v2 v

get /v1/v2

stat /v1/v2

cZxid = 0x1a
ctime = Mon Sep 02 17:02:01 CST 2019
mZxid = 0x1a
mtime = Mon Sep 02 17:02:01 CST 2019
pZxid = 0x1a
cversion = 0
dataVersion = 0
aclVersion = 0
ephemeralOwner = 0x0
dataLength = 1
numChildren = 0

解釋說明：

cZxid ：創建znode更改的事務ID
ctime ：znode創建時間
mZxid ：最後修改znode更改的事務ID
mtime ：最近修改時間
pZxid ：用於添加或刪除子節點的znode更改的事務ID
cversion ：對此znode的子節點進行的更改次數
dataVersion ：對該znode的數據所做的更改次數
aclVersion ：對此znode的ACL進行更改的次數
ephemeralOwner ：如果znode是ephemeral類型節點，則這是znode所有者的 session ID。 如果znode不是ephemeral節點，則該字段設置爲零。
dataLength ：znode數據字段的長度
numChildren ：znode的子節點的數量

create [-s] [-e] [-c] [-t ttl] path [data] [acl]
-s sequential 序列化的，即可以重複創建，在路徑後面加上序列號
-e ephemeral 臨時的，斷開連接後自動失效

create /v2
create -s /v2/v3
create -s /v2/v3
create -s /v2/v3

ls /v2
[v30000000000, v30000000001, v30000000002]

java zookeeper

maven依賴

<dependency>
    <groupId>org.apache.zookeeper</groupId>
    <artifactId>zookeeper</artifactId>
    <version>3.5.5</version>
</dependency>

public class ZookeeperServer {

    CountDownLatch countDownLatch = new CountDownLatch(1);

    private ZooKeeper zooKeeper = null;

    private ZooKeeper connectServer(String... zkServerUrl) {
        ZooKeeper zk = null;
        try {
            zk = new ZooKeeper(Arrays.asList(zkServerUrl).stream().collect(Collectors.joining(",")), 3000, new Watcher() {
                @Override
                public void process(WatchedEvent watchedEvent) {
                    if (watchedEvent.getState() == Event.KeeperState.SyncConnected) {
                        // 連接成功
                        countDownLatch.countDown();
                    }

                    // ...
                }
            });

            // 等待
            countDownLatch.await();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return zk;
    }

    public ZookeeperServer(String... zkServerUrl) {
        this.zooKeeper = connectServer(zkServerUrl);
	}

	public ZooKeeper getZooKeeper() {
        return this.zooKeeper;
    }
}