zookeeper操作 - 软件仓

##Zookeeper 简单命令
	./zkServer.sh start					  #启动
	./zkServer.sh stop					   #停止
	./zkServer.sh status					 #查看 ZK 状态
	./zkCli.sh -server 127.0.0.1:2181		#使用 zkCli 连接

##操作 node 命令
	#查看命令
	help
	#展示某节点下所有节点
	ls /			
---
	#创建节点
	create 节点 节点值 eg： create /zk_test my_data		
	#创建临时节点。注意：断开重连之后，临时节点自动消失
	create -e
	#创建顺序节点。
	create -s
---
	#递归删除
	rmr 节点
	#删除节点
	delete 节点 eg：delete /zk_test
---
	#获取节点值
	get 节点 eg：get /zk_test
---
	#更新节点的值
	set 节点 新值 eg: set /zk_test junk

###set path data [version] 修改节点
####注意：如不添加[version]，则dataVersion默认会自增加
	[zk: localhost:2181(CONNECTED) 6] get /merryyou
	merryyou
	cZxid = 0x200000004
	ctime = Sat Jun 02 14:20:06 UTC 2018
	mZxid = 0x200000004
	mtime = Sat Jun 02 14:20:06 UTC 2018
	pZxid = 0x200000009
	cversion = 4
	dataVersion = 0
	aclVersion = 0
	ephemeralOwner = 0x0
	dataLength = 8
	numChildren = 2
	# 修改节点内容为new-merryyou
	[zk: localhost:2181(CONNECTED) 7] set /merryyou new-merryyou
	cZxid = 0x200000004
	ctime = Sat Jun 02 14:20:06 UTC 2018
	mZxid = 0x20000000a
	mtime = Sat Jun 02 14:29:23 UTC 2018
	pZxid = 0x200000009
	cversion = 4
	dataVersion = 1
	aclVersion = 0
	ephemeralOwner = 0x0
	dataLength = 12
	numChildren = 2
	#再次查询，节点内容已经修改
	[zk: localhost:2181(CONNECTED) 8] get /merryyou
	new-merryyou
	cZxid = 0x200000004
	ctime = Sat Jun 02 14:20:06 UTC 2018
	mZxid = 0x20000000a
	mtime = Sat Jun 02 14:29:23 UTC 2018
	pZxid = 0x200000009
	cversion = 4
	dataVersion = 1
	aclVersion = 0
	ephemeralOwner = 0x0
	dataLength = 12
	numChildren = 2
	#set 根据版本号更新 dataVersion 乐观锁
	[zk: localhost:2181(CONNECTED) 9] set /merryyou test-merryyou 1
	cZxid = 0x200000004
	ctime = Sat Jun 02 14:20:06 UTC 2018
	mZxid = 0x20000000b
	mtime = Sat Jun 02 14:31:30 UTC 2018
	pZxid = 0x200000009
	cversion = 4
	dataVersion = 2
	aclVersion = 0
	ephemeralOwner = 0x0
	dataLength = 13
	numChildren = 2
	#因为数据的版本号已经修改为2 再次使用版本号1修改节点提交错误
	[zk: localhost:2181(CONNECTED) 10] set /merryyou test-merryyou 1
	version No is not valid : /merryyou