ZooKeeper-API CURD

ZooKeeper Java API

pom.xml 依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <parent>
        <artifactId>root</artifactId>
        <groupId>jhxxb</groupId>
        <version>1.0-SNAPSHOT</version>
        <relativePath>../root/pom.xml</relativePath>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>zookeeper</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.apache.zookeeper</groupId>
            <artifactId>zookeeper</artifactId>
            <version>3.4.14</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <!-- 指定jdk -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

测试代码

public class ZooKeeperTest {
    // 集群地址
    // private String connectString = "192.168.8.138:2181,192.168.8.136:2181,192.168.8.140:2181";
    private String connectString = "127.0.0.1:2181";
    private int sessionTimeout = 5000;
    private ZooKeeper zk;

    @Before
    public void init() throws IOException {
        BasicConfigurator.configure();
        zk = new ZooKeeper(connectString, sessionTimeout, new Watcher() {
            @Override
            public void process(WatchedEvent event) {

            }
        });
    }

    @After
    public void close() throws InterruptedException {
        zk.close();
    }

    @Test
    public void create() throws KeeperException, InterruptedException {
        // 创建节点
        System.out.println(zk.create("/zhongguo", "hubei".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT));
    }

    @Test
    public void getChildren() throws KeeperException, InterruptedException {
        // 获取节点
        System.out.println(zk.getChildren("/", false));
    }

    @Test
    public void getData() throws KeeperException, InterruptedException {
        // 获取节点数据
        System.out.println(new String(zk.getData("/zhongguo", false, zk.exists("/zhongguo", false))));
    }

    @Test
    public void exists() throws KeeperException, InterruptedException {
        // 判断节点是否存在
        Stat stat = zk.exists("/zhongguo", false);
        System.out.println(stat == null ? "not exist" : "exist");
    }

    @Test
    public void setData() throws KeeperException, InterruptedException {
        // 修改子目录节点数据
        System.out.println(zk.setData("/zhongguo", "beijing".getBytes(), -1));
    }

    @Test
    public void delete() throws Exception {
        // 删除空节点目录
        //zk.delete("/zhongguo", -1);
        // 删除父节点目录
        rmr("/dubbo");
    }

    /**
     * 递归删除，zookeeper 只允许删除叶子节点（空节点）
     */
    public void rmr(String path) throws Exception {
        // 获取路径下的节点
        List<String> children = zk.getChildren(path, false);
        for (String pathCd : children) {
            // 获取父节点下面的子节点路径
            String newPath = "";
            // 递归调用,判断是否是根节点
            if (path.equals("/")) {
                newPath = "/" + pathCd;
            } else {
                newPath = path + "/" + pathCd;
            }
            rmr(newPath);
        }
        // 删除节点,并过滤 zookeeper 节点和 / 节点
        if (path != null && !path.trim().startsWith("/zookeeper") && !path.trim().equals("/")) {
            zk.delete(path, -1);
            // 打印删除的节点路径
            System.out.println("删除节点：" + path);
        }
    }
}

---

http://zookeeper.apache.org/doc/r3.4.14/api/index.html