ZooKeeper第三方客户端CuratorFramework简介

结论:在使用CuratorFramework的监听机制时,

    如果使用NodeCache,对于多级路径,即使不创建该路径,设置监听后CuratorFramework会主动创建从第一级路径到倒数第二级的路径,比如要监听路径 "/a/b/c" 的NodeCache,CuratorFramework会自动替你创建路径 "/a/b";

    如果使用PathChildrenCache,对于多级路径,即使不创建该路径,设置监听后CuratorFramework会主动创建整个完整路径,比如要监听路径 "/A/B/C" 的PathChildrenCache,CuratorFramework会自动替你创建路径 "/A/B/C"。

测试代码:





启动程序前,ZooKeeper的节点情况:

[zk: localhost:2181(CONNECTED) 2] ls /

[cluster, brokers, zookeeper, admin, isr_change_notification, log_dir_event_notification, controller_epoch, name, ha, consumers, latest_producer_id_block, config]

节点中并不包含"/A"和"/a"这两个。


启动程序后,ZooKeeper的节点情况:

[zk: localhost:2181(CONNECTED) 3] ls /

[cluster, a, A, brokers, zookeeper, admin, isr_change_notification, log_dir_event_notification, controller_epoch, name, ha, consumers, latest_producer_id_block, config]

再查看其具体路径:

[zk: localhost:2181(CONNECTED) 4] get /a/b


cZxid = 0x125b

ctime = Sun Sep 09 12:43:02 GMT+08:00 2018

mZxid = 0x125b

mtime = Sun Sep 09 12:43:02 GMT+08:00 2018

pZxid = 0x125b

cversion = 0

dataVersion = 0

aclVersion = 0

ephemeralOwner = 0x0

dataLength = 0

numChildren = 0

[zk: localhost:2181(CONNECTED) 5] get /a/b/c

Node does not exist: /a/b/c

[zk: localhost:2181(CONNECTED) 6] get /A/B/C


cZxid = 0x125e

ctime = Sun Sep 09 12:43:02 GMT+08:00 2018

mZxid = 0x125e

mtime = Sun Sep 09 12:43:02 GMT+08:00 2018

pZxid = 0x125e

cversion = 0

dataVersion = 0

aclVersion = 0

ephemeralOwner = 0x0

dataLength = 0

numChildren = 0


可以看出,确实和结论一样。

上一篇:教你利用Python把图片转字符画!代码哆啦A梦你见过嘛?


下一篇:【OpenIM原创】简单轻松入门 一文讲解WebRTC实现1对1音视频通信原理