Jedis
Jedis
使用Java操作redis
Jedis是redis官方推荐的Java连接开发工具！ 使用Java操作redis的中间件
测试
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导入对应的依赖
<dependency> <groupId>redis.clientsgroupId> <artifactId>jedisartifactId> <version>4.4.3version> dependency> <dependency> <groupId>com.alibaba.fastjson2groupId> <artifactId>fastjson2artifactId> <version>2.0.39version> dependency> -
编码测试
- 连接数据库
- 操作命令
- 断开连接
public class TestPing {
public static void main(String[] args) {
// 1. new Jedis 对象
Jedis jedis = new Jedis("8.130.104.8",6379);
System.out.println(jedis.ping());
}
}
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常用API
对key的操作
public class TestKey {
public static void main(String[] args) {
Jedis jedis = new Jedis("8.130.104.8", 6379);
System.out.println("清空数据："+jedis.flushDB());
System.out.println("判断某个键是否存在："+jedis.exists("username"));
System.out.println("新增<'username','kuangshen'>的键值对："+jedis.set("username", "kuangshen"));
System.out.println("新增<'password','password'>的键值对："+jedis.set("password", "password"));
System.out.print("系统中所有的键如下：");
Set<String> keys = jedis.keys("*");
System.out.println(keys);
System.out.println("删除键password:"+jedis.del("password"));
System.out.println("判断键password是否存在："+jedis.exists("password"));
System.out.println("查看键username所存储的值的类型："+jedis.type("username"));
System.out.println("随机返回key空间的一个："+jedis.randomKey());
System.out.println("重命名key："+jedis.rename("username","name"));
System.out.println("取出改后的name："+jedis.get("name"));
System.out.println("按索引查询："+jedis.select(0));
System.out.println("删除当前选择数据库中的所有key："+jedis.flushDB());
System.out.println("返回当前数据库中key的数目："+jedis.dbSize());
System.out.println("删除所有数据库中的所有key："+jedis.flushAll());
}
}
String
public class TestString {
public static void main(String[] args) {
Jedis jedis = new Jedis("8.130.104.8", 6379);
jedis.flushDB();
System.out.println("===========增加数据===========");
System.out.println(jedis.set("key1","value1"));
System.out.println(jedis.set("key2","value2"));
System.out.println(jedis.set("key3", "value3"));
System.out.println("删除键key2:"+jedis.del("key2"));
System.out.println("获取键key2:"+jedis.get("key2"));
System.out.println("修改key1:"+jedis.set("key1", "value1Changed"));
System.out.println("获取key1的值："+jedis.get("key1"));
System.out.println("在key3后面加入值："+jedis.append("key3", "End"));
System.out.println("key3的值："+jedis.get("key3"));
System.out.println("增加多个键值对："+jedis.mset("key01","value01","key02","value02","key03","value03"));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03","key04"));
System.out.println("删除多个键值对："+jedis.del("key01","key02"));
System.out.println("获取多个键值对："+jedis.mget("key01","key02","key03"));
jedis.flushDB();
System.out.println("===========新增键值对防止覆盖原先值==============");
System.out.println(jedis.setnx("key1", "value1"));
System.out.println(jedis.setnx("key2", "value2"));
System.out.println(jedis.setnx("key2", "value2-new"));
System.out.println(jedis.get("key1"));
System.out.println(jedis.get("key2"));
System.out.println("===========新增键值对并设置有效时间=============");
System.out.println(jedis.setex("key3", 2, "value3"));
System.out.println(jedis.get("key3"));
try {
TimeUnit.SECONDS.sleep(3);
} catch (InterruptedException e) {
e.printStackTrace();
}
System.out.println(jedis.get("key3"));
System.out.println("===========获取原值，更新为新值==========");
System.out.println(jedis.getSet("key2", "key2GetSet"));
System.out.println(jedis.get("key2"));
System.out.println("获得key2的值的字串："+jedis.getrange("key2", 2, 4));
}
}
List
public class TestList {
public static void main(String[] args) {
Jedis jedis = new Jedis("8.130.104.8", 6379);
jedis.flushDB();
System.out.println("===========添加一个list===========");
jedis.lpush("collections", "ArrayList", "Vector", "Stack", "HashMap", "WeakHashMap", "LinkedHashMap");
jedis.lpush("collections", "HashSet");
jedis.lpush("collections", "TreeSet");
jedis.lpush("collections", "TreeMap");
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));//-1代表倒数第一个元素，-2代表倒数第二个元素,end为-1表示查询全部
System.out.println("collections区间0-3的元素："+jedis.lrange("collections",0,3));
System.out.println("===============================");
// 删除列表指定的值 ，第二个参数为删除的个数（有重复时），后add进去的值先被删，类似于出栈
System.out.println("删除指定元素个数："+jedis.lrem("collections", 2, "HashMap"));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("删除下表0-3区间之外的元素："+jedis.ltrim("collections", 0, 3));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("collections列表出栈（左端）："+jedis.lpop("collections"));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("collections添加元素，从列表右端，与lpush相对应："+jedis.rpush("collections", "EnumMap"));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("collections列表出栈（右端）："+jedis.rpop("collections"));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("修改collections指定下标1的内容："+jedis.lset("collections", 1, "LinkedArrayList"));
System.out.println("collections的内容："+jedis.lrange("collections", 0, -1));
System.out.println("===============================");
System.out.println("collections的长度："+jedis.llen("collections"));
System.out.println("获取collections下标为2的元素："+jedis.lindex("collections", 2));
System.out.println("===============================");
jedis.lpush("sortedList", "3","6","2","0","7","4");
System.out.println("sortedList排序前："+jedis.lrange("sortedList", 0, -1));
System.out.println(jedis.sort("sortedList"));
System.out.println("sortedList排序后："+jedis.lrange("sortedList", 0, -1));
}
}
Set
public class TestSet {
public static void main(String[] args) {
Jedis jedis = new Jedis("8.130.104.8", 6379);
jedis.flushDB();
System.out.println("============向集合中添加元素（不重复）============");
System.out.println(jedis.sadd("eleSet", "e1","e2","e4","e3","e0","e8","e7","e5"));
System.out.println(jedis.sadd("eleSet", "e6"));
System.out.println(jedis.sadd("eleSet", "e6"));
System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
System.out.println("删除一个元素e0："+jedis.srem("eleSet", "e0"));
System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
System.out.println("删除两个元素e7和e6："+jedis.srem("eleSet", "e7","e6"));
System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
System.out.println("随机的移除集合中的一个元素："+jedis.spop("eleSet"));
System.out.println("eleSet的所有元素为："+jedis.smembers("eleSet"));
System.out.println("eleSet中包含元素的个数："+jedis.scard("eleSet"));
System.out.println("e3是否在eleSet中："+jedis.sismember("eleSet", "e3"));
System.out.println("e1是否在eleSet中："+jedis.sismember("eleSet", "e1"));
System.out.println("e1是否在eleSet中："+jedis.sismember("eleSet", "e5"));
System.out.println("=================================");
System.out.println(jedis.sadd("eleSet1", "e1","e2","e4","e3","e0","e8","e7","e5"));
System.out.println(jedis.sadd("eleSet2", "e1","e2","e4","e3","e0","e8"));
System.out.println("将eleSet1中删除e1并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e1"));//移到集合元素
System.out.println("将eleSet1中删除e2并存入eleSet3中："+jedis.smove("eleSet1", "eleSet3", "e2"));
System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
System.out.println("eleSet3中的元素："+jedis.smembers("eleSet3"));
System.out.println("============集合运算=================");
System.out.println("eleSet1中的元素："+jedis.smembers("eleSet1"));
System.out.println("eleSet2中的元素："+jedis.smembers("eleSet2"));
System.out.println("eleSet1和eleSet2的交集:"+jedis.sinter("eleSet1","eleSet2"));
System.out.println("eleSet1和eleSet2的并集:"+jedis.sunion("eleSet1","eleSet2"));
System.out.println("eleSet1和eleSet2的差集:"+jedis.sdiff("eleSet1","eleSet2"));//eleSet1中有，eleSet2中没有
jedis.sinterstore("eleSet4","eleSet1","eleSet2");//求交集并将交集保存到dstkey的集合
System.out.println("eleSet4中的元素："+jedis.smembers("eleSet4"));
}
}
Hash
public class TestHash {
public static void main(String[] args) {
Jedis jedis = new Jedis("8.130.104.8", 6379);
jedis.flushDB();
Map<String,String> map = new HashMap<String,String>();
map.put("key1","value1");
map.put("key2","value2");
map.put("key3","value3");
map.put("key4","value4");
//添加名称为hash（key）的hash元素
jedis.hmset("hash",map);
//向名称为hash的hash中添加key为key5，value为value5元素
jedis.hset("hash", "key5", "value5");
System.out.println("散列hash的所有键值对为："+jedis.hgetAll("hash"));//return MapZset
事务操作
public class TestMulti {
public static void main(String[] args) {
//创建客户端连接服务端，redis服务端需要被开启
Jedis jedis = new Jedis("8.130.104.8", 6379);
jedis.flushDB();
JSONObject jsonObject = new JSONObject();
jsonObject.put("hello","world");
jsonObject.put("name","zs");
// 开启事务
Transaction multi = jedis.multi();
String result = jsonObject.toJSONString();
try {
multi.set("user1",result);
multi.set("user2",result);
int i = 1/0; // 代码抛出异常，事务执行失败
multi.exec(); // 执行事务
} catch (Exception e) {
//如果出现异常，回滚
multi.discard(); // 放弃事务
throw new RuntimeException(e);
} finally {
System.out.println(jedis.get("user1"));
System.out.println(jedis.get("user2"));
//最终关闭客户端
jedis.close();
}
}
}