etcd的java客户端

  <properties>        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>        <java.version>1.8</java.version>        <maven.compiler.source>1.8</maven.compiler.source>        <maven.compiler.target>1.8</maven.compiler.target>  </properties>  <dependencies>    <dependency>      <groupId>com.coreos</groupId>      <artifactId>jetcd-core</artifactId>      <version>0.0.2</version>    </dependency>    <dependency>      <groupId>org.slf4j</groupId>      <artifactId>slf4j-log4j12</artifactId>      <version>1.7.25</version>    </dependency>    <dependency>      <groupId>log4j</groupId>      <artifactId>log4j</artifactId>      <version>1.2.17</version>    </dependency>    <dependency>      <groupId>org.slf4j</groupId>      <artifactId>slf4j-api</artifactId>      <version>1.7.25</version>    </dependency>    <dependency>      <groupId>org.slf4j</groupId>      <artifactId>slf4j-nop</artifactId>      <version>1.7.25</version>    </dependency>    <dependency>      <groupId>org.slf4j</groupId>      <artifactId>slf4j-simple</artifactId>      <version>1.7.5</version>    </dependency>  </dependencies>  <build>    <plugins>      <plugin>            <groupId>org.apache.maven.plugins</groupId>              <artifactId>maven-assembly-plugin</artifactId>              <version>2.5.5</version>              <configuration>                  <archive>                      <manifest>                          <mainClass>com.xxg.Main</mainClass>                      </manifest>                  </archive>                  <descriptorRefs>                      <descriptorRef>jar-with-dependencies</descriptorRef>                  </descriptorRefs>              </configuration>          </plugin>    </plugins>  </build>package com.gemdale.iot;import com.coreos.jetcd.Client;import com.coreos.jetcd.KV;import com.coreos.jetcd.Watch;import com.coreos.jetcd.data.ByteSequence;import com.coreos.jetcd.data.KeyValue;import java.util.List;public class EtcdUtil1 {    // etcd客户端链接    private static Client client = null;    private static String IPPORT = null;    static {        IPPORT = System.getProperty("IPPORT", "http://10.34.4.47:11000");        getEtcdClient();    }    // 链接初始化    public static Client getEtcdClient() {        if (client == null) {            synchronized (EtcdUtil1.class) {                client = Client.builder().lazyInitialization(false).endpoints(IPPORT).build();            }        }        return client;    }    /**     * 根据指定的配置名称获取对应的value     *      * @param key     *            配置项     * @return     * @throws Exception     */    public static String getEtcdValueByKey(String key) throws Exception {        KeyValue kv = getEtcdKeyValueByKey(key);        if (kv != null) {            return kv.getValue().toStringUtf8();        } else {            return null;        }    }    /**     * 根据指定的配置名称获取对应的keyvalue     *      * @param key     *            配置项     * @return     * @throws Exception     */    public static KeyValue getEtcdKeyValueByKey(String key) throws Exception {        KV kvCient = client.getKVClient();        List<KeyValue> kvs = kvCient.get(ByteSequence.fromString(key)).get().getKvs();        kvCient.close();        if (kvs.size() > 0) {            return kvs.get(0);        } else {            return null;        }    }    /**     * 新增或者修改指定的配置     *      * @param key     * @param value     * @return     */    public static void putEtcdValueByKey(String key, String value) throws Exception {        client.getKVClient().put(ByteSequence.fromString(key), ByteSequence.fromBytes(value.getBytes("utf-8")));    }    /**     * 删除指定的配置     *      * @param key     * @return     */    public static void deleteEtcdValueByKey(String key) {        client.getKVClient().delete(ByteSequence.fromString(key));    }    // V3 api配置初始化和监听    public void init() {        try {            // 加载配置            getConfig(client.getKVClient().get(ByteSequence.fromString("test")).get().getKvs());            // 启动监听线程            new Thread(() -> {                // 对某一个配置进行监听                Watch.Watcher watcher = client.getWatchClient().watch(ByteSequence.fromString("etcd_key"));                try {                    while (true) {                        watcher.listen().getEvents().stream().forEach(watchEvent -> {                            KeyValue kv = watchEvent.getKeyValue();                            // 获取事件变化类型                            System.out.println(watchEvent.getEventType());                            // 获取发生变化的key                            System.out.println(kv.getKey().toStringUtf8());                            // 获取变化后的value                            String afterChangeValue = kv.getValue().toStringUtf8();                        });                    }                } catch (InterruptedException e) {                    e.printStackTrace();                }            }).start();        } catch (Exception e) {            e.printStackTrace();        }    }    private String getConfig(List<KeyValue> kvs) {        if (kvs.size() > 0) {            String config = kvs.get(0).getValue().toStringUtf8();            System.out.println("etcd 's config 's configValue is :" + config);            return config;        } else {            return null;        }    }}