Redis的java客户端Jedis

第0章:简介

(1)maven配置:

       
            redis.clients
            jedis
            2.1.0
            jar
            compile
       

(2)简单测试

Jedis jedis = new Jedis("localhost");
jedis.set("foo","bar");
String value = jedis.get("foo");

(3)参考网站

Jedis官网:https://github.com/xetorthio/jedis

Jedis开源中国:http://www.oschina.net/p/jedis

大V博客:http://snowolf.iteye.com/blog/1633196


(4)札记

1)目前Redis大概有3中基于Java语言的Client,分别是Jredis,Jedis,Redis4J,这里只说Jedis,因为它是官方提供的唯一Redis Client For Java Provider。

第1章:Jedis实践

这里假设Redis已经正常运行,redis的具体安装可以参考“Redis基础”章节。下面就2.1.0版jedis作为redis的java客户端进行封装和测试,具体如下:

(1)Redis客户端(RedisClient.java)

package com.mcc.core.redis;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import redis.clients.jedis.*;
import redis.clients.jedis.exceptions.JedisConnectionException;
import redis.clients.util.Slowlog;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

/**
 * Redis客户端,基于Jedis,用到jedis包
 * 单列模式, 建议应用与Redis集群部署在同一台服务器上,以获得最佳性能
 *
 * @author menergy
 *         DateTime: 13-12-21  下午2:09
 */
public class RedisClient {
    // members
    private static Logger logger = LoggerFactory.getLogger(RedisClient.class);
    // 单例
    private static RedisClient instance;
    // 默认超时时间
    private int defaultTimeout = 10000;
    // Redis集群,写节点,Master
    private JedisPool masterPool;
    // 默认Master IP
    private String masterHost = "127.0.0.1";
    // 默认端口
    private int masterPort = 6379;
    // Redis集群, 读节点,Slaves
    private Map slavePools;
    //
    private static int poolIndex = 1;
    // 连接密码
    private String password;
    // 当前数据库
    private int database;
    // Redis Master Server 状态 -1 : 连接失败,0 : 未连接,1 : 连接成功
    private int writeStatus = 0;
    // Redis slave Server 状态 -1 : 连接失败,0 : 未连接,1 : 连接成功
    private int readStatus = 0;
    //
    private int delayRetry = 10;
    //
    private AliveEventListener aliveEventListener;
    //
    private ExecutorService executor;

    // static block

    // constructors

    /**
     * 默认构造器

     * 当应用与Redis集群为同一台服务器时使用
     */
    private RedisClient() {
        this("127.0.0.1", 6379);
    }

    /**
     * 指定Master实例地址端口

     * 当应用与Redis集群为不同服务器时使用,如开发测试时
     *
     * @param host Master IP
     * @param port Master PORT
     */
    private RedisClient(String host, int port) {
        this(host, port, null, 0);
    }

    /**
     * 指定Master实例地址端口,密码,数据库

     * 适用一套Redis集群支撑多套应用
     *
     * @param host     Master IP
     * @param port     Master PORT
     * @param password Redis密码
     * @param database 数据库
     */
    private RedisClient(String host, int port, String password, Integer database) {
        this.masterHost = host;
        this.masterPort = port;
        this.password = password != null && password.isEmpty() ? null : password;
        this.database = database == null ? 0 : database;
        // 连接集群
        this.connectRedis();
        this.executor = Executors.newFixedThreadPool(2, new SubscribeThreadFactory());
        // 检查集群是否在线
        this.checkAlive();
    }

    // properties

    public int getDatabase() {
        return database;
    }

    /**
     * 是否可以写入状态
     *
     * @return 写入状态
     */
    public int getWriteStatus() {
        return writeStatus;
    }

    /**
     * 是否可以读入状态
     *
     * @return 读入状态
     */
    public int getReadStatus() {
        return readStatus;
    }

    /**
     * 存活事件
     *
     * @param aliveEventListener
     */
    public void setAliveEventListener(AliveEventListener aliveEventListener) {
        this.aliveEventListener = aliveEventListener;
    }

    // public methods

    /**
     * 获得取实例
     *
     * @return 返回一个Client实例
     */
    public static RedisClient getInstance() {
        if (instance == null) {
            instance = new RedisClient();
        }
        return instance;
    }

    /**
     * 获得取实例
     *
     * @param host Master IP
     * @param port Master PORT
     * @return 返回一个Client实例
     */
    public static RedisClient getInstance(String host, int port) {
        if (instance == null) {
            instance = new RedisClient(host, port);
        }
        return instance;
    }

    /**
     * 获得取实例
     *
     * @param host     Master IP
     * @param port     Master PORT
     * @param password 连接密码, 允许空
     * @return 返回一个Client实例
     */
    public static RedisClient getInstance(String host, int port, String password) {
        if (instance == null) {
            instance = new RedisClient(host, port, password, 0);
        }
        return instance;
    }

    /**
     * 获得取实例
     *
     * @param host     Master IP
     * @param port     Master PORT
     * @param password 连接密码, 允许空
     * @param database 数据库
     * @return 返回一个Client实例
     */
    public static RedisClient getInstance(String host, Integer port, String password, Integer database) {
        if (instance == null) {
            instance = new RedisClient(host, port, password, database);
        }
        return instance;
    }

    /**
     * 获得SlavePool
     *
     * @return 返回slave连接池
     */
    public JedisPool getSlavePool() {
        JedisPool pool = slavePools.get(poolIndex);
        poolIndex += 1;
        if (poolIndex > slavePools.size()) poolIndex = 1;
        return pool;
    }

    /**
     * 检查给定 key 是否存在
     *
     * @param key 键
     * @return 若 key 存在,返回 1 ,否则返回 0
     */
    public boolean exists(final String key) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.exists(key);
            }
        });
        return actual != null ? (Boolean) actual : false;
    }

    /**
     * 查看哈希表 key 中,给定域 field 是否存在
     *
     * @param key   键
     * @param field 域
     * @return 如果哈希表含有给定域,返回 1, 若不含有给定域,或 key 不存在,返回 0
     */
    public boolean hexists(final String key, final String field) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hexists(key, field);
            }
        });
        return actual != null ? (Boolean) actual : false;
    }

    /**
     * 返回哈希表 key 中给定域 field 的值
     *
     * @param key   键
     * @param field 域
     * @return 给定域的值, 当给定域不存在或是给定 key 不存在时,返回 nil
     */
    public String hget(final String key, final String field) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hget(key, field);
            }
        });
        return actual != null ? actual.toString() : null;
    }

    /**
     * 返回哈希表 key 中域的数量
     *
     * @param key 键
     * @return 哈希表中域的数量, 当 key 不存在时,返回 0
     */
    public Long hlen(final String key) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hlen(key);
            }
        });
        return actual != null ? Long.valueOf(actual.toString()) : null;
    }

    /**
     * 返回哈希表 key 中的所有域
     *
     * @param key 键
     * @return 一个包含哈希表中所有域的表, 当 key 不存在时,返回一个空表
     */
    public Set hkeys(final String key) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hkeys(key);
            }
        });
        return actual != null ? (Set) actual : null;
    }

    /**
     * 返回哈希表 key 中所有域的值
     *
     * @param key 键
     * @return 一个包含哈希表中所有值的表, 当 key 不存在时,返回一个空表
     */
    public List hvals(final String key) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hvals(key);
            }
        });
        return actual != null ? (List) actual : null;
    }

    /**
     * 返回哈希表 key 中,所有的域和值
     *
     * @param key 键
     * @return 以列表形式返回哈希表的域和域的值, 若 key 不存在,返回空列表
     */
    public Map hgetAll(final String key) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.hgetAll(key);
            }
        });
        return actual != null ? (Map) actual : null;
    }

    /**
     * 查找所有符合给定模式 pattern 的 key

     *


     * KEYS * 匹配数据库中所有 key 。
     * KEYS h?llo 匹配 hello , hallo 和 hxllo 等。
     * KEYS h*llo 匹配 hllo 和 heeeeello 等。
     * KEYS h[ae]llo 匹配 hello 和 hallo ,但不匹配 hillo
     *

     *
     * @param pattern 模式
     * @return 符合给定模式的 key 列表
     */
    public Set keys(final String pattern) {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.keys(pattern);
            }
        });
        return actual != null ? (Set) actual : null;
    }

    /**
     * 删除给定的一个或多个 key

     * 不存在的 key 会被忽略
     *
     * @param keys 缓存名称
     * @return 被删除 key 的数量
     */
    public Long del(final String... keys) {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.del(keys);
            }
        });
        return actual != null ? (Long) actual : null;
    }

    /**
     * 将信息 message 发送到指定的频道 channel
     *
     * @param channel 频道
     * @param command 指令
     * @param message 指令内容
     * @return
     */
    public Long publish(final String channel, final String command, final String message) {
        long actual = 0;
        if (command != null && message != null) {
            actual = publish(channel, String.format("%s %s", command, message));
        }
        return actual;
    }

    /**
     * 将信息 message 发送到指定的频道 channel
     *
     * @param channel 频道
     * @param message 信息
     * @return
     */
    public Long publish(final String channel, final String message) {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.publish(channel, message);
            }
        });
        return actual != null ? (Long) actual : 0;
    }


    /**
     * 从频道channels订阅信息message

     * 订阅会阻塞进程,因此开一个新线程来执行, 注意不要频繁调用该方法
     *
     * @param handler  消息处理器
     * @param channels 频道
     */
    public void subscribe(final JedisPubSub handler, final String... channels) {
        // 订阅会阻塞进程,因此开一个新线程来执行
        executor.execute(new Runnable() {
            @Override
            public void run() {
                int delayRetry = 10;
                JedisShardInfo info = new JedisShardInfo(masterHost, masterPort, defaultTimeout);
                if (password != null) {
                    info.setPassword(password);
                }
                // jedis.select(database); 每个Redis Server只有一套订阅,与数据库无关,不需要关注select 那个database
                while (true) {
                    try {
                        Jedis jedis = new Jedis(info);
                        jedis.subscribe(handler, channels);
                    } catch (JedisConnectionException e) {
                        writeStatus = -1;
                        if (logger.isErrorEnabled()) {
                            logger.error("redis db connection reset ! please check it , {} second after reconnect !", delayRetry);
                        }
                        sleep(delayRetry);
                    }
                }
            }
        });
    }

    /**
     * 查看Redis数据库连接是否正常
     *
     * @return 返回是否正常
     */
    public boolean pingMaster() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                String pong = null;
                try {
                    pong = jedis.ping();
                } catch (Exception ignored) {
                }
                return pong;
            }
        });
        return true;
    }

    /**
     * 查看Redis数据库连接是否正常
     *
     * @return 返回是否正常
     */
    public boolean pingSlave() {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                String pong = null;
                try {
                    pong = jedis.ping();
                } catch (Exception ignored) {
                }
                return pong;
            }
        });
        return true;
    }

    /**
     * 返回当前数据库的 key 的数量
     *
     * @return 当前数据库的 key 的数量
     */
    public Long dbSize() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.dbSize();
            }
        });

        return actual != null ? (Long) actual : null;
    }

    /**
     * 执行一个 AOF文件 重写操作
     *
     * @return Status code reply
     */
    public String bgrewriteaof() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.bgrewriteaof();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 保存当前数据库的数据到磁盘
     *
     * @return Status code reply
     */
    public String bgsave() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.bgsave();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 将当前 Redis 实例的所有数据快照(snapshot)以 RDB 文件的形式保存到硬盘(采用同步方式,一般不用)
     *
     * @return Status code reply
     */
    public String save() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.save();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 获得最近一次 Redis 成功将数据保存到磁盘的时间
     *
     * @return Status code reply
     */
    public Long lastSave() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.lastsave();
            }
        });
        return actual != null ? (Long) actual : null;
    }

    /**
     * 将当前服务器转变为指定服务器的从属服务器(slave server)
     *
     * @param host 从属服务器ip
     * @param port 从属服务器端口
     * @return Status code reply
     */
    public String slaveof(final String host, final Integer port) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slaveof(host, port);
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 关闭从属服务器的复制功能
     *
     * @return Status code reply
     */
    public String slaveofNoOne() {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slaveofNoOne();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 清空整个 Redis 服务器的数据(删除所有数据库的所有 key ,此命令从不失败)
     *
     * @return Status code reply
     */
    public String flushAll() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.flushAll();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 清空当前数据库中的所有 key(此命令从不失败)
     *
     * @return Status code reply
     */
    public String flushDB() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.flushDB();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 停止所有客户端
     *
     * @return Status code reply
     */
    public String shutdown() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.shutdown();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 获取查询日志
     *
     * @return Status code reply
     */
    public List slowlogGet() {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slowlogGet();
            }
        });
        return actual != null ? (List) actual : null;
    }

    /**
     * 获取指定数量的查询日志
     *
     * @param entries 日志数量
     * @return 日志
     */
    public List slowlogGet(final Long entries) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slowlogGet(entries);
            }
        });
        return actual != null ? (List) actual : null;
    }

    /**
     * 查看当前日志的数量
     *
     * @return 当前日志的数量
     */
    public Long slowlogLen() {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slowlogLen();
            }
        });
        return actual != null ? (Long) actual : null;
    }

    /**
     * 清空日志
     *
     * @return 清空日志
     */
    public byte[] slowlogReset() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.slowlogReset();
            }
        });
        return actual != null ? (byte[]) actual : null;
    }

    /**
     * 返回关于 Redis 服务器的各种信息和统计值
     *
     * @return Redis 服务器的各种信息和统计值
     */
    public String info() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.info();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 获取服务器的配置参数
     *
     * @param pattern 参数
     * @return 参数表
     */
    public List configGet(final String pattern) {
        Object actual = slave(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.configGet(pattern);
            }
        });
        return actual != null ? (List) actual : null;
    }

    /**
     * 动态改变服务器参数(无需重启,即刻生效)
     *
     * @param parameter 参数名
     * @param value     参数值
     * @return Status code reply
     */
    public String configSet(final String parameter, final String value) {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.configSet(parameter, value);
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * 重置 INFO 命令中的某些统计数据
     *
     * @return Status code reply
     */
    public String configResetstart() {
        Object actual = master(new Action() {
            @Override
            public Object execute(final Jedis jedis) {
                return jedis.configResetStat();
            }
        });
        return actual != null ? (String) actual : null;
    }

    /**
     * Redis查询,保证只从Slave查询
     *
     * @param action 操作
     * @return 返回查询结果
     */
    public Object slave(Action action) {
        Object actual = null;
        if (slaveOnline()) {
            JedisPool pool = null;
            Jedis jedis = null;
            try {
                pool = this.getSlavePool();
                if (pool != null) {
                    jedis = pool.getResource();
                    actual = action.execute(jedis);
                } else {
                    this.readStatus = -1;
                }
            } catch (JedisConnectionException e) {
                int osize = slavePools.size();
                initSlaves(getDefaultConfig());
                int nsize = slavePools.size();
                this.readStatus = slavePools.isEmpty() ? -1 : 1;
                if (osize != nsize && logger.isErrorEnabled()) {
                    logger.error("slave instance size changed! {} to {}", osize, nsize);
                }
            } finally {
                if (pool != null) {
                    pool.returnResource(jedis);
                }
            }
        }
        return actual;
    }

    /**
     * 更新或插入数据,只从Master写入数据

     * 若要使用方式Jedis的select方法临时切换数据库,请使用该方法
     *
     * @param action 操作
     * @return 返回操作结果
     */
    public Object master(Action action) {
        Object actual = null;
        if (masterOnline()) {
            JedisPool pool = null;
            Jedis jedis = null;
            try {
                pool = this.getMasterPool();
                jedis = pool.getResource();
                actual = action.execute(jedis);
            } catch (JedisConnectionException e) {
                this.writeStatus = -1;
                if (logger.isErrorEnabled()) {
                    logger.error("redis db connection reset ! please checkAlive it !");
                }
            } finally {
                if (pool != null) {
                    pool.returnResource(jedis);
                }
            }
        }
        return actual;
    }

    // protected methods

    /**
     * 获得MasterPool
     *
     * @return
     */
    public JedisPool getMasterPool() {
        return masterPool;
    }

    // friendly methods

    // private methods

    /**
     * master配置
     *
     * @param config 配置
     */
    private void initMaster(JedisPoolConfig config) {
        try {
            masterPool = new JedisPool(config, this.masterHost, this.masterPort, this.defaultTimeout, this.password, this.database);
            Jedis jedis = masterPool.getResource();
            jedis.ping();
            masterPool.returnResource(jedis);
            writeStatus = 1;
            if (logger.isInfoEnabled()) {
                logger.info("redis master connected !");
            }
        } catch (JedisConnectionException e) {
            writeStatus = -1;
            if (logger.isErrorEnabled()) {
                logger.error("redis master connection reset ! please check it , {} second after reconnect !", delayRetry);
            }
        }
    }

    /**
     * slave配置
     *
     * @param config 配置
     */
    private void initSlaves(final JedisPoolConfig config) {
        if (masterPool != null) {
            slavePools = new HashMap();
            master(new Action() {
                @Override
                public Object execute(Jedis jedis) {
                    String info = jedis.info();
                    String[] lines = info.split("\r\n");
                    for (String line : lines) {
                        if (line.contains("slave") && line.contains("online")) {
                            String[] online = line.split(":")[1].split(",");
                            String host = online[0];
                            String port = online[1];
                            // 处理当应用与redis不在同一台服务器上的情况
                            if("127.0.0.1".equalsIgnoreCase(host)){
                                host = masterHost;
                            }
                            jedis.hset("redis.slave", host, port);
                            JedisPool pool = null;
                            Jedis slave = null;
                            try {
                                pool = new JedisPool(config, host, Integer.valueOf(port), defaultTimeout, password, database);
                                slave = pool.getResource();
                                slavePools.put(slavePools.size() + 1, pool);
                            } catch (JedisConnectionException e) {
                                if (logger.isErrorEnabled()) {
                                    logger.error("slave: {}", e.getMessage());
                                }
                            } finally {
                                if (pool != null && slave != null) {
                                    pool.returnResource(slave);
                                }
                            }
                        }
                    }
                    // 更新slave节点状态
                    readStatus = !slavePools.isEmpty() ? 1 : -1;
                    switch (readStatus) {
                        case -1:
                            if (logger.isErrorEnabled()) {
                                logger.error("redis slave connection reset ! please check it , {} second after reconnect !", delayRetry);
                            }
                            break;
                        case 1:
                            if (logger.isInfoEnabled()) {
                                logger.info("redis slave connected!");
                            }
                            break;
                    }
                    return readStatus;
                }
            });
        }
    }

    /**
     * 返回一个默认的JedisPoolConfig
     *
     * @return 返回一个默认的JedisPoolConfig
     */
    private JedisPoolConfig getDefaultConfig() {
        // 连接配置
        JedisPoolConfig config = new JedisPoolConfig();
        config.setMaxActive(100);
        config.setMaxIdle(20);
        config.setMaxWait(10000);
        // 设定在借出对象时是否进行有效性检查
        config.setTestOnBorrow(true);
        return config;
    }

    /**
     * 连接Redis Cluster
     */
    private void connectRedis() {
        if (writeStatus != 1) {
            initMaster(getDefaultConfig());
            initSlaves(getDefaultConfig());
        }
        if (readStatus != 1) {
            initSlaves(getDefaultConfig());
        }
        // 解发事件
        if (this.aliveEventListener != null) {
            this.aliveEventListener.onEvents(masterOnline(), slaveOnline());
        }
    }

    /**
     * 检查集群是否存活
     *
     * @return
     */
    private void checkAlive() {
        executor.execute(new Runnable() {
            @Override
            public void run() {
                while (true) {
                    try {
                        connectRedis();
                        sleep(delayRetry);
                    } catch (JedisConnectionException e) {
                        if (logger.isErrorEnabled()) {
                            logger.error("redis db connection reset ! please check it , {} second after reconnect !", delayRetry);
                        }
                        sleep(delayRetry);
                    }
                }
            }
        });
    }

    /**
     * Master连接池是否在线
     *
     * @return 若没初化成功则返回 false, 若成功则返回 true
     */
    private boolean masterOnline() {
        return this.writeStatus == 1;
    }


    /**
     * Slave连接池是否在线
     *
     * @return 若没初化成功则返回 false, 若成功则返回 true
     */
    private boolean slaveOnline() {
        return this.readStatus == 1;
    }

    /**
     * 休眠指定时间
     *
     * @param second 休眠秒数
     */
    private void sleep(int second) {
        try {
            TimeUnit.SECONDS.sleep(second);
        } catch (InterruptedException ignored) {
        }
    }

    // inner class

    /**
     * Redis Cluster 存活状态发生变化事件监听器
     */
    public interface AliveEventListener {
        /**
         * Redis Cluster 存活状态发生变化事件

         * 每十秒触发一次
         *
         * @param masterAlive Redis Master Server是否存活
         * @param slaveAlive  Redis Slave Server 是否存活
         */
        void onEvents(boolean masterAlive, boolean slaveAlive);
    }
    // test main

}

(2)Jedis查询接口(Action.java)

package com.mcc.core.redis;

import redis.clients.jedis.Jedis;

/**
 * Jedis查询接口
 *
 * @author menergy
 *         DateTime: 13-12-21  下午2:28
 */
public interface Action {
    /**
     * Redis 通用查询
     *
     * @param jedis redis客户端
     * @return
     */
    Object execute(final Jedis jedis);
}


(3)Redis命令的发布订阅(CommandHandler.java)

package com.mcc.core.redis;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import redis.clients.jedis.JedisPubSub;

/**
 * 通过Redis的发布订阅机制实现实时指令控制台
 *
 * @author menergy
 *         DateTime: 13-12-21  下午2:34
 */
public class CommandHandler extends JedisPubSub {

    private static Logger logger = LoggerFactory.getLogger(CommandHandler.class);

    //频道,也可以用配置文件配置
    public static final String COMMAND_CHANNEL = "execute";
    //命令,可以自定义命令
    public static final String COMMAND = "loadall";

    /**
     * 指令频道名称
     */
    private String channel;

    /**
     * 指令消息
     */
    private String message;


    public CommandHandler() {

    }

    /**
     * 处理指令消息事件
     *
     * @param channel 指令频道名称
     * @param message 指令消息
     */
    @Override
    public void onMessage(String channel, String message) {
        this.channel = channel;
        this.message = message;
        try {
            if (channel != null && channel.equalsIgnoreCase(COMMAND_CHANNEL)) {
                if (message != null && !message.isEmpty()) {
                    String cmd = message, content = "";
                    int length = message.length(), delimiter = message.indexOf(" ");
                    if (delimiter != -1) {
                        int start = delimiter + 1 > length ? length : delimiter + 1;
                        cmd = message.substring(0, delimiter); // 指令
                        content = message.substring(start, length); // 指令内容
                    }
                    // 更新全部缓存
                    if (cmd.equalsIgnoreCase(COMMAND)) {
                        logger.info("该命令下的操作逻辑");
                        //执行该命令下的相应操作,具体这里暂不实现
                    }
                }
            }
        } catch (Exception e) {
            if (logger.isErrorEnabled()) {
                logger.error("failure to execute command '{}' , cause: {}!", message, e.getMessage());
            }
        }
    }

    @Override
    public void onPMessage(String pattern, String channel, String message) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onPSubscribe(String pattern, int subscribedChannels) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onPUnsubscribe(String pattern, int subscribedChannels) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onSubscribe(String channel, int subscribedChannels) {
        // TODO Auto-generated method stub

    }

    @Override
    public void onUnsubscribe(String channel, int subscribedChannels) {
        // TODO Auto-generated method stub

    }

    public String getChannel() {
        return channel;
    }

    public void setChannel(String channel) {
        this.channel = channel;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }
}


(4)异常处理类(SubscribeThreadFactory.java)

package com.mcc.core.redis;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.concurrent.ThreadFactory;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;

/**
 * 带异常处处理器的ThreaFactory
 *
 * @author menergy
 *         DateTime: 13-12-21  下午2:19
 */
public class SubscribeThreadFactory implements ThreadFactory {

    // members
    private static Logger logger = LoggerFactory.getLogger(SubscribeThreadFactory.class);
    static final AtomicInteger poolCounter = new AtomicInteger(1);
    final AtomicLong threadCounter = new AtomicLong(1);
    final ThreadGroup group;
    final String namingPattern;
    // static block

    // constructors
    public SubscribeThreadFactory() {
        SecurityManager securityManager = System.getSecurityManager();
        group = (securityManager != null) ? securityManager.getThreadGroup() : Thread.currentThread().getThreadGroup();
        namingPattern = "redis-" + poolCounter.getAndIncrement() + "-subscribe-thread-";
    }
    // properties

    // public methods

    @Override
    public Thread newThread(Runnable r) {
        Thread worker = new Thread(group, r, namingPattern + threadCounter.getAndIncrement(), 0);
        worker.setUncaughtExceptionHandler(new Thread.UncaughtExceptionHandler() {
            @Override
            public void uncaughtException(Thread t, Throwable e) {
                if (logger.isErrorEnabled()) {
                    logger.error(e.getMessage(), e);
                }
            }
        });
        if (worker.isDaemon()) {
            worker.setDaemon(false);
        }
        if (worker.getPriority() != Thread.NORM_PRIORITY) {
            worker.setPriority(Thread.NORM_PRIORITY);
        }
        return worker;
    }

    // protected methods

    // friendly methods

    // private methods

    // inner class

    // test main
}


(5)Jedis客户端测试类(RedisTest.java)

package com.mcc.core.test;


import com.mcc.core.redis.CommandHandler;
import com.mcc.core.redis.RedisClient;

import java.util.concurrent.atomic.AtomicBoolean;

/**
 * redis测试类
 *
 * @author menergy
 *         DateTime: 13-12-21  下午2:51
 */
public class RedisTest {


    public static void main() {
        final RedisClient redisClient = RedisClient.getInstance("192.168.8.69", 6379, "", 1);

        //
        final AtomicBoolean needLoad = new AtomicBoolean(true);
        // 监听Redis Cluster 存活状态
        redisClient.setAliveEventListener(new RedisClient.AliveEventListener() {
            /**
             * Redis Cluster 存活状态发生变化事件

             * 每十秒触发一次
             *
             * @param masterAlive Redis Master Server是否存活
             * @param slaveAlive  Redis Slave Server 是否存活
             */
            @Override
            public void onEvents(boolean masterAlive, boolean slaveAlive) {
                if (masterAlive) {
                    // 确认Redis Cluster 后初始化配置
                    if (needLoad.get()) {
                        // 通过Redis的发布订阅实现指令系统
                        CommandHandler handler = new CommandHandler();
                        // 指令信道名称
                        String channel = CommandHandler.COMMAND_CHANNEL;
                        // 注册指令信道服务
                        redisClient.publish(channel, "");
                        // 订阅并监听指令信道
                        redisClient.subscribe(handler, channel);
                        // 标记为已配置
                        needLoad.set(false);
                    }
                } else {
                    // 继续等待Redis Cluster存活通知
                }
            }
        });
    }
}




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