Curator Tutorial (i) Quick start

Curator is a zookeeper client of Netflix's open source, and curator has a higher level of abstraction than the native client provided by zookeeper, simplifying zookeeper client programming.

It contains the following components:

Component	Description
Recipes	Implementations of some of the common zookeeper "recipes". The implementations are built on the top of the curator Framework.
Framework	The curator Framework is a high-level API that greatly simplifies using zookeeper. It adds many features that builds on zookeeper and handles the complexity of managing connections to the Zookeeper and retrying operations.
Utilities	Various utilities that are useful when using zookeeper.
Client	A replacement for the bundled zookeeper class that takes care of some low-level housekeeping and provides some useful Ities.
Errors	How to curator deals with errors, connection issues, recoverable exceptions, etc.
Extensions	The Curator-recipes package implements the common recipes are described in the zookeeper. To avoid bloating the package, recipes/applications that have a vertical appeal would be put in separate "extension" packa GES using the naming convention Curator-x-name.

Environment ConfigurationJDK 1.7 Zookeeper 3.4.8 curator 2.11.1 Maven 3.3 Quick Start maven Dependencies

<properties> <java.version>1.7</java.version> <curator.version>2.11.1</ curator.version> </properties> <dependencies> <dependency> <groupid>org.apache.zoo 
        Keeper</groupid> <artifactId>zookeeper</artifactId> <version>3.4.8</version> <exclusions> <exclusion> &LT;ARTIFACTID&GT;SLF4J-LOG4J12&LT;/ARTIFACTID&G
                T <groupId>org.slf4j</groupId> </exclusion> <exclusion> < 
        Artifactid>log4j</artifactid> <groupId>log4j</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupId>org.apache.curator< /groupid> <artifactId>curator-framework</artifactId> <version>${curator.version}</ Version> </dependency> <dependency> <groupId>org.apache.curator</groupId> <artifactId>
            Curator-client</artifactid> <version>${curator.version}</version> <exclusions> <exclusion> <groupId>com.google.guava</groupId> <artifactid& gt;guava</artifactid> </exclusion> </exclusions> </dependency> <de
        Pendency> <groupId>com.google.guava</groupId> <artifactId>guava</artifactId> <version>18.0</version> </dependency> </dependencies>

1. Create a curator connection instance

String address = "localhost:2181";
Curatorframework client = curatorframeworkfactory.newclient (address, new Exponentialbackoffretry (1000, 3));

Note: A zookeeper cluster only needs to construct a Curatorframework instance object.

Curatorframework must first be invoked before using the

Client.start ();

After you complete a series of actions, call Client.close (), and you can use the try-finally statement:

Curatorframework client = curatorframeworkfactory.newclient (address, new Exponentialbackoffretry (1000, 3));
try{
    Client.start ();
    ...
} Finally {
    if (client!=null)
        client.close ();
}

2. Create a node

A. Creating a permanent node

Client.create ()
      . creatingparentcontainersifneeded ().
      Withmode (createmode.persistent).
      Withacl ( ZooDefs.Ids.OPEN_ACL_UNSAFE)
      . Forpath (Path, "Hello, ZK". GetBytes ());

B. Creating a temporary node

Client.create (). Withmode (createmode.ephemeral). Forpath (Path, "Hello". GetBytes ());  

3. Get the node value

byte[] buf = Client.getdata (). Forpath (path);
SYSTEM.OUT.PRINTLN ("Get Data path:" +path+ ", Data:" +new String (BUF));

4. Set node value

Client.setdata (). Inbackground (). Forpath (Path, "Ricky". GetBytes ());

5.checkExists

Stat Stat = client.checkexists (). Forpath (path);
if (stat==null) {
    System.out.println ("Exec Create path:" +path);
} else {
    System.out.println ("exec getData");
}

6. Delete node

Client.delete (). deletingchildrenifneeded (). Forpath ("/pandora");

Click here to download the complete code: Https://github.com/TiFG/zookeeper-samples Reference

Getting started:http://curator.apache.org/getting-started.html