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非关系型数据库redis-java基本操作

概述

      redis 是一个 key-value 的 nosql 数据库 (非关系型数据库)。支持存储的 value 类型包括 string(字符串)、list(链表)、set(集合)、zset(sorted set -- 有序集合) 和 hash（哈希类型）。这些数据类型都支持 push/pop、add/remove 及取交集并集和差集及更丰富的操作，而且这些操作都是原子性的。为了保证效率，数据都是缓存在内存中。

下载 Windows 版 Redis

Redis 官网不支持 Windows，可以去 Github 上下载，可以直接下载 zip 解压即可。

Redis 客户端软件：https://redisdesktop.com/

指定配置启动，可以在 conf 文件中配置密码等选项。

./redis-server.exe redis.windows.conf

启动后可以看到端口和 PID，当然也可以在后台启动。

用 redis-cli.exe -h 127.0.0.1 -p 6379 连接 redis 服务。

 

redis 执行语句

redis 的命令:各种命令在这里

包下载

       关于 java 操作 redis 的 jar 包可以使用Jedis, 当然下载这个是要 FQ 的啦,FQ 的话同志们可以去买各种 vpn, 也可以自己搭,自己搭建 VPN 服务器的话看这里, 都嫌麻烦可以用 lantern. 还嫌麻烦的话度娘那也有.

代码

redis 因为是非关系型数据库, 所以没有表的概念, 而且也没有 sql 语句.

public class RedisJava {
    Jedis jedis = new Jedis("222.222.221.137",6379); //连接本地的 Redis 服务
    public static void main(String[] args) {
        RedisJava redisJava = new RedisJava();
        System.out.println("服务正在运行:"+redisJava.jedis.ping());
        redisJava.save("sk1", "-value1");
        redisJava.update("sk1", "sk111");
        redisJava.findByKey("sk111");
        redisJava.del("sk111");
        redisJava.findAll();
        redisJava.list();
        redisJava.map();
        redisJava.set();
　　　　 redisJava.jedis.disconnect();}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">添加数据(key/value)</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> save(String key,String value){
    String result </span>=<span style="color: rgba(0, 0, 0, 1)"> jedis.set(key, value);
    System.out.println(</span>"添加{"+key+":"+value+"},结果为"+<span style="color: rgba(0, 0, 0, 1)">result);
}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">根据Key查询数据</span>
<span style="color: rgba(0, 0, 255, 1)">public</span><span style="color: rgba(0, 0, 0, 1)"> String findByKey(String key){
    String value </span>=<span style="color: rgba(0, 0, 0, 1)"> jedis.get(key);
    System.out.println(</span>"get到"+key+"的值为"+<span style="color: rgba(0, 0, 0, 1)">value);
    </span><span style="color: rgba(0, 0, 255, 1)">return</span><span style="color: rgba(0, 0, 0, 1)"> value;
}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">修改key</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> update(String oldKey,String newKey){
    System.out.println(</span>"检测是否有key:"+oldKey+",结果为:"+<span style="color: rgba(0, 0, 0, 1)">jedis.exists(oldKey));
    jedis.rename(oldKey, newKey);
    System.out.println(</span>"将key:"+oldKey+"重置为"+<span style="color: rgba(0, 0, 0, 1)">newKey);
}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">根据Key删除数据</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> del(String key) {
   Long result </span>=<span style="color: rgba(0, 0, 0, 1)"> jedis.del(key);
   System.out.println(</span>"删除的结果为:"+<span style="color: rgba(0, 0, 0, 1)">result);
}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">查询所有</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> findAll(){
    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)"> 获取keys数据并输出</span>
    Set&lt;String&gt; keys = jedis.keys("*"<span style="color: rgba(0, 0, 0, 1)">);
    Iterator</span>&lt;String&gt; it=<span style="color: rgba(0, 0, 0, 1)">keys.iterator();
    System.out.println(</span>"所有key:"<span style="color: rgba(0, 0, 0, 1)">);
    </span><span style="color: rgba(0, 0, 255, 1)">while</span><span style="color: rgba(0, 0, 0, 1)">(it.hasNext()){   
        String key </span>=<span style="color: rgba(0, 0, 0, 1)"> it.next();   
        System.out.println(key);   
        jedis.del(key);    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">删除所有key</span>



        }
}


</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">操作List</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> list() {
    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">存储数据到列表中,一条一条存</span>
    jedis.lpush("list", "FireFox"<span style="color: rgba(0, 0, 0, 1)">);
    jedis.lpush(</span>"list", "Google"<span style="color: rgba(0, 0, 0, 1)">);
    jedis.lpush(</span>"list", "IE"<span style="color: rgba(0, 0, 0, 1)">);
    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)"> 从头添加,一次添加多条</span>
    jedis.lpush("list", "flash", "cisco", "catalin", "Google"<span style="color: rgba(0, 0, 0, 1)">);
    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)"> 从尾添加</span>
    jedis.rpush("list", "walley", "jon"<span style="color: rgba(0, 0, 0, 1)">);

    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)"> 返回List长度</span>
    System.out.println("list长度为:"+jedis.llen("list"<span style="color: rgba(0, 0, 0, 1)">));

    </span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)"> 取值</span>
    System.out.println("所有list:"<span style="color: rgba(0, 0, 0, 1)">);
    List</span>&lt;String&gt; list = jedis.lrange("list", 0, -1<span style="color: rgba(0, 0, 0, 1)">);
    </span><span style="color: rgba(0, 0, 255, 1)">for</span><span style="color: rgba(0, 0, 0, 1)"> (String string : list) {
        System.out.println(string);
    }
}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">操作Map</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> map() {
    jedis.hset(</span>"Mcity", "c1", "上海"); <span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">key,map-key,map-value</span>
    System.out.println("取值：" + jedis.hget("Mcity", "c1"));   <span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">根据key,map-key,获取mapvalue</span>
    Map&lt;String, String&gt; map = <span style="color: rgba(0, 0, 255, 1)">new</span> HashMap&lt;String, String&gt;<span style="color: rgba(0, 0, 0, 1)">();
    map.put(</span>"c1", "徐州");   <span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">相同的map-key会被覆盖</span>
    map.put("c2", "扬州"<span style="color: rgba(0, 0, 0, 1)">);
    map.put(</span>"c3", "常州"<span style="color: rgba(0, 0, 0, 1)">);
    jedis.hmset(</span>"Mcity", map);   <span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">一次取多个map值</span>



        List<String> list = jedis.hmget("Mcity", "c1", "c2", "c3");  //一次获取多个 map-value
        for (String string : list) {System.out.println(string);
        }
        System.out.println("list 长度:"+jedis.hlen("Mcity"));}

</span><span style="color: rgba(0, 128, 0, 1)">//</span><span style="color: rgba(0, 128, 0, 1)">操作Set</span>
<span style="color: rgba(0, 0, 255, 1)">public</span> <span style="color: rgba(0, 0, 255, 1)">void</span><span style="color: rgba(0, 0, 0, 1)"> set() {
    jedis.sadd(</span>"city", "扬州", "上海", "南京", "苏州", "徐州", "常州","北京"<span style="color: rgba(0, 0, 0, 1)">);
    System.out.println(</span>"取最上面的值:" + jedis.spop("city"<span style="color: rgba(0, 0, 0, 1)">));
    System.out.println(</span>"随机取值:" + jedis.srandmember("city"<span style="color: rgba(0, 0, 0, 1)">));
    jedis.sadd(</span>"city1", "北京", "上海", "河北", "辽林", "云南", "黑龙江"<span style="color: rgba(0, 0, 0, 1)">);
    System.out.println(</span>"交集：" + jedis.sinter("city", "city1"<span style="color: rgba(0, 0, 0, 1)">));
    System.out.println(</span>"并集：" + jedis.sunion("city", "city1"<span style="color: rgba(0, 0, 0, 1)">));
    System.out.println(</span>"差集：" + jedis.sdiff("city", "city1"<span style="color: rgba(0, 0, 0, 1)">));
}



}

源码(其实 jar 包这里也有啦)