SpringBoot开发二十-Redis入门以及Spring整合Redis

安装 Redis,熟悉 Redis 的命令以及整合Redis,在Spring 中使用Redis。

代码实现

Redis 内置了 16 个库,索引是 0-15 ,默认选择第 0 个

Redis 的常用命令:

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40

select 1

flushdb

Keys *

String 类型数据的操作:

set k1 1
// 获得key的值
get k1
// 删除key的值
del k1
// 对key值自增自减
incr k1
decr k1

hash 类型数据的操作:
// 设置key的值
格式是:hset hash的key 项的key 项的值
例如:hset myhash id 1
// 设置多对key值
格式是:hmset hash的key 项的key 项的值
例如:hmset myhash id 1 name xixi
// 获取key的值
格式是:hget hash的key 项的key
例如:hget myhash id
// 获取多对key的值
格式是:hmget hash的key 项的key
例如:hmget myhash id name
// 获取该key下所有的值
格式是:hgetall hash的key
例如:hgetall myhash
// 如果项不存在则赋值,存在时什么都不做
格式是:hsetnx Hash的key 项的key 项的值
例如:hsetnx myhash address earth
// 判断键值是否存在
格式是:hexists hash的key 项的key
例如:hexists myhash id

Spring 引入 Redis

首先要在 pom.xml 引入依赖

1
2
3
4
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

然后需要对 Redis 进行配置,要在配置文档 application.properties 里面配置数据库的参数。

1
2
3
4
# RedisProperties
spring.redis.database=11
spring.redis.host=localhost
spring.redis.port=6379

然后要编写配置类来构造RedisTemplate。其实呢SpringBoot 也对Redis进行了配置RedisTemplate,但是由于Redis是一个key-value的数据库,它在做的时候把key配置成了Object类型,但是由于我们一般都用String,所以重新配置一下。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
package com.nowcoder.community.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.RedisSerializer;


public class {
// 我们要通过 Template 访问数据库,那么它要想具备访问数据库的能力就要能创建连接,而连接又是由连接工厂创建的,所以要把连接工厂注入进来

public RedisTemplate<String, Object> (RedisConnectionFactory redisConnectionFactory) {
RedisTemplate<String, Object> template = new RedisTemplate<>();
// 使得Template有访问数据库的能力
template.setConnectionFactory(redisConnectionFactory);

// 设置key的序列化的方式
template.setKeySerializer(RedisSerializer.string());
// 设置value的序列化方式
template.setValueSerializer(RedisSerializer.json());
// 设置hash的key的序列化的方式
template.setHashKeySerializer(RedisSerializer.string());
// 设置hash的value的序列化的方式
template.setHashValueSerializer(RedisSerializer.json());

template.afterPropertiesSet();
return template;
}
}

然后访问数据的时候就是以下用法:

1
2
3
4
5
redisTemplate.opsForValue(); // 访问String
redisTemplate.opsForHash(); // 访问Hash
redisTemplate.opsForList(); // 访问List
redisTemplate.opsForSet(); // 访问Set
redisTemplate.opsForZSet(); // 访问ZSet

现在就可以通过 RedisTemplate 来访问Redis数据库,来添加删除数据。

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
10 大专栏  SpringBoot开发二十-Redis入门以及Spring整合Redis6
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
package com.nowcoder.community;

import org.aspectj.lang.annotation.Aspect;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.core.BoundValueOperations;
import org.springframework.data.redis.core.RedisOperations;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.SessionCallback;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.concurrent.TimeUnit;

@RunWith(SpringRunner.class)
@SpringBootTest
@ContextConfiguration(classes = CommunityApplication.class)
public class RedisTests {
@Autowired
private RedisTemplate redisTemplate;

@Test
public void testStrings() {
String redisKey = "test:count";
redisTemplate.opsForValue().set(redisKey, 1);
System.out.println(redisTemplate.opsForValue().get(redisKey));
System.out.println(redisTemplate.opsForValue().increment(redisKey));
System.out.println(redisTemplate.opsForValue().decrement(redisKey));
}

@Test
public void testHashes() {
String redisKey = "test:user";

redisTemplate.opsForHash().put(redisKey, "id", 1);
redisTemplate.opsForHash().put(redisKey, "username", "zhangsan");

System.out.println(redisTemplate.opsForHash().get(redisKey, "id"));
System.out.println(redisTemplate.opsForHash().get(redisKey, "username"));
}

@Test
public void testLists() {
String redisKey = "test:ids";

redisTemplate.opsForList().leftPush(redisKey, 101);
redisTemplate.opsForList().leftPush(redisKey, 102);
redisTemplate.opsForList().leftPush(redisKey, 103);

System.out.println(redisTemplate.opsForList().size(redisKey));
System.out.println(redisTemplate.opsForList().index(redisKey, 0));
System.out.println(redisTemplate.opsForList().range(redisKey, 0, 2));

// 从左边弹出,左边leftpop,右边rightpop
System.out.println(redisTemplate.opsForList().leftPop(redisKey));
System.out.println(redisTemplate.opsForList().leftPop(redisKey));
System.out.println(redisTemplate.opsForList().leftPop(redisKey));
}

@Test
public void testSets() {
String redisKey = "test:teachers";

redisTemplate.opsForSet().add(redisKey, "刘备", "关羽", "张飞", "赵云", "诸葛亮");

System.out.println(redisTemplate.opsForSet().size(redisKey));
System.out.println(redisTemplate.opsForSet().pop(redisKey));
System.out.println(redisTemplate.opsForSet().members(redisKey));
}

@Test
public void testSortedSets() {
String redisKey = "test:students";

redisTemplate.opsForZSet().add(redisKey, "唐僧", 80);
redisTemplate.opsForZSet().add(redisKey, "悟空", 90);
redisTemplate.opsForZSet().add(redisKey, "八戒", 50);
redisTemplate.opsForZSet().add(redisKey, "沙僧", 70);
redisTemplate.opsForZSet().add(redisKey, "白龙马", 60);

// 统计数据
System.out.println(redisTemplate.opsForZSet().zCard(redisKey));
// 查询某个人的分数
System.out.println(redisTemplate.opsForZSet().score(redisKey, "八戒"));
// 查询排名,默认从小到大
System.out.println(redisTemplate.opsForZSet().reverseRank(redisKey, "八戒"));
// 查询区间排名数据
System.out.println(redisTemplate.opsForZSet().reverseRange(redisKey, 0, 2));
}

@Test
public void testKeys() {
redisTemplate.delete("test:user");

System.out.println(redisTemplate.hasKey("test:user"));

redisTemplate.expire("test:students", 10, TimeUnit.SECONDS);
}

// 多次访问同一个key
@Test
public void testBoundOperations() {
String redisKey = "test:count";
BoundValueOperations operations = redisTemplate.boundValueOps(redisKey);
operations.increment();
operations.increment();
operations.increment();
operations.increment();
operations.increment();
System.out.println(operations.get());
}

// Redis编程序事务,并不一定满足我们之前说过的事务,因为不是关系型数据库
@Test
public void testTransactional() {
Object obj = redisTemplate.execute(new SessionCallback() {
@Override
public Object execute(RedisOperations operations) throws DataAccessException {
String redisKey = "test:tx";
// 启用事务
operations.multi();

operations.opsForSet().add(redisKey, "zhangsan");
operations.opsForSet().add(redisKey, "lisi");
operations.opsForSet().add(redisKey, "wangwu");

System.out.println(operations.opsForSet().members(redisKey));
// 提交事务
return operations.exec();
}
});
System.out.println(obj);
}
}

猜你喜欢

转载自www.cnblogs.com/lijianming180/p/12014228.html