Springboot2.0访问Redis集群
Redis 是一个开源（BSD许可）的，内存中的数据结构存储系统，它可以用作高性能的key-value数据库、缓存和消息中间件，掌握它是程序员的必备技能，下面是一个springboot访问redis的demo。
新建一个springboot项目，这里取名spring-boot-demo
项目结构目录如下
pom.xml文件内容
<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.carry</groupId> <artifactId>spring-boot-demo</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>spring-boot-demo</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.2.RELEASE</version> <relativePath /> <!-- lookup parent from repository --> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> <mybatis.version>1.3.2</mybatis.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-redis</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>${mybatis.version}</version> </dependency> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <fork>true</fork> </configuration> </plugin> </plugins> </build> </project>
下面我们来配置redis，因为需要用到mysql数据库，这里使用mybatis访问
application.yml文件内容
#mybatis配置
mybatis:
mapper-locations: classpath:mapper/*Mapper.xml
type-aliases-package: com.carry.domain
#数据源
spring:
datasource:
url: jdbc:mysql://192.168.68.100:3306/test
driver-class-name: com.mysql.jdbc.Driver
username: root
password: 123456
#jackson时间格式化
jackson:
time-zone: GMT+8
date-format: yyyy-MM-dd HH:mm:ss
#redis配置
redis:
cluster:
nodes: 192.168.68.100:7000,192.168.68.100:7001,192.168.68.101:7000,192.168.68.101:7001,192.168.68.102:7000,192.168.68.102:7001
timeout: 6000ms
password: 123456
lettuce:
pool:
max-active: 8
max-wait: -1ms
max-idle: 8
min-idle: 0
database: 0
新建文件RedisConfig.java，内容如下
package com.carry.config;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
import org.springframework.boot.autoconfigure.data.redis.RedisAutoConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
@Configuration
@AutoConfigureAfter(RedisAutoConfiguration.class)
public class RedisConfig {
@Bean
public RedisTemplate<String, Object> redisCacheTemplate(LettuceConnectionFactory redisConnectionFactory) {
//redis序列化器
Jackson2JsonRedisSerializer<Object> jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<>(Object.class);
ObjectMapper om = new ObjectMapper();
om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
jackson2JsonRedisSerializer.setObjectMapper(om);
RedisTemplate<String, Object> template = new RedisTemplate<>();
template.setConnectionFactory(redisConnectionFactory);
template.setKeySerializer(jackson2JsonRedisSerializer);
template.setValueSerializer(jackson2JsonRedisSerializer);
template.setHashKeySerializer(jackson2JsonRedisSerializer);
template.setHashValueSerializer(jackson2JsonRedisSerializer);
return template;
}
}
最后在项目启动类SpringBootDemoApplication上加上注解@EnableCaching开启缓存
配置至此结束，下面我们来通过代码来访问redis集群
先写一个访问mysql的mapper，其中只包含一个方法List<User> findAll();
对应SQL语句为select * from user
User实体类跟user表字段一一对应
UserServiceImpl代码内容
package com.carry.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.stereotype.Service;
import com.carry.domain.User;
import com.carry.mapper.UserMapper;
import com.carry.service.UserService;
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserMapper userMapper;
@Cacheable(value = "findAll", key = "'test'")
public List<User> findAll() {
System.out.println("如果没打印这句话，说明走了缓存！");
return userMapper.findAll();
}
}
UserController代码内容
package com.carry.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import com.carry.domain.User;
import com.carry.service.UserService;
@RestController
public class UserController {
@Autowired
private UserService userService;
@GetMapping("/getUsers")
public List<User> getUsers(){
return userService.findAll();
}
}
最后启动项目在浏览器中访问http://localhost:8080/getUsers
第一次访问控制台输出“如果没打印这句话，说明走了缓存！”
再次访问控制台则没有输出。
我们通过redis-cli连接redis会发现key值是一个很奇怪的值
其实就是我们在@Cacheable注解配的值拼起来的
需要注意的是key的值需要用单引号''引起来不然会报错
最后写了几个test case，读者自己去运行看看控制台会输出什么
1 package com.carry;
2
3 import java.util.Date;
4 import java.util.HashSet;
5 import java.util.List;
6 import java.util.Map;
7 import java.util.Set;
8 import java.util.concurrent.ExecutorService;
9 import java.util.concurrent.Executors;
10 import java.util.stream.IntStream;
11
12 import org.junit.Test;
13 import org.junit.runner.RunWith;
14 import org.slf4j.Logger;
15 import org.slf4j.LoggerFactory;
16 import org.springframework.beans.factory.annotation.Autowired;
17 import org.springframework.boot.test.context.SpringBootTest;
18 import org.springframework.data.redis.core.Cursor;
19 import org.springframework.data.redis.core.DefaultTypedTuple;
20 import org.springframework.data.redis.core.HashOperations;
21 import org.springframework.data.redis.core.ListOperations;
22 import org.springframework.data.redis.core.RedisTemplate;
23 import org.springframework.data.redis.core.ScanOptions;
24 import org.springframework.data.redis.core.SetOperations;
25 import org.springframework.data.redis.core.StringRedisTemplate;
26 import org.springframework.data.redis.core.ValueOperations;
27 import org.springframework.data.redis.core.ZSetOperations;
28 import org.springframework.test.context.junit4.SpringRunner;
29
30 import com.carry.domain.User;
31
32 @RunWith(SpringRunner.class)
33 @SpringBootTest
34 public class SpringBootDemoApplicationTests {
35
36 private static final Logger log = LoggerFactory.getLogger(SpringBootDemoApplicationTests.class);
37
38
39 @Autowired
40 private StringRedisTemplate stringRedisTemplate;
41
42 @Autowired
43 private RedisTemplate<String, Object> redisCacheTemplate;
44
45
46 @Test
47 public void redisTest() {
48 ExecutorService executorService = Executors.newFixedThreadPool(1000);
49 IntStream.range(0, 1000).forEach(i ->
50 executorService.execute(() -> stringRedisTemplate.opsForValue().increment("kk", 1))
51 );
52 }
53
54 @Test
55 public void redisTestString() {
56 stringRedisTemplate.opsForValue().set("carry", "chan");
57 final String v1 = stringRedisTemplate.opsForValue().get("carry");
58 log.info("[字符缓存结果] - [{}]", v1);
59 }
60
61 @Test
62 public void redisTestObject() {
63 //以下只演示整合，具体Redis命令可以参考官方文档，Spring Data Redis 只是改了个名字而已，Redis支持的命令它都支持
64 String key = "carry:user:1";
65 ValueOperations<String, Object> valueOperations = redisCacheTemplate.opsForValue();
66 valueOperations.set(key, new User(1, "carry", new Date(), "longhua"));
67 //对应 String（字符串）
68 final User user = (User) valueOperations.get(key);
69 log.info("[对象缓存结果] - [{}]", user);
70 }
71
72 @Test
73 public void redisTestList() {
74 ListOperations<String, Object> listOperations = redisCacheTemplate.opsForList();
75 listOperations.trim("key1", 1, 0);
76 List<Object> list = listOperations.range("key1", 0, -1);
77 log.info("[对象缓存结果] - {}", list);
78 listOperations.leftPush("key1", 1);
79 listOperations.leftPush("key1", 2);
80 listOperations.rightPush("key1", 3);
81 list = listOperations.range("key1", 0, -1);
82 log.info("[对象缓存结果] - {}", list);
83 }
84
85 @Test
86 public void redisTestHash() {
87 HashOperations<String, Object, Object> hashOperations = redisCacheTemplate.opsForHash();
88 hashOperations.put("hkey", "k1", "v1");
89 hashOperations.put("hkey", "k2", "v2");
90 hashOperations.put("hkey", "k3", "v3");
91 Map<Object, Object> map = hashOperations.entries("hkey");
92 log.info("[对象缓存结果] - [{}]", map);
93 }
94
95 @Test
96 public void redisTestSet() {
97 SetOperations<String, Object> setOperations = redisCacheTemplate.opsForSet();
98 setOperations.add("skey", "v1", "v2", "v3", "v4");
99 Cursor<Object> cursor = setOperations.scan("skey", ScanOptions.NONE);
100 while (cursor.hasNext()) {
101 System.out.println(cursor.next());
102 }
103 log.info("[对象缓存结果] - [{}]", cursor);
104 }
105
106 @Test
107 public void redisTestZSet() {
108 ZSetOperations<String, Object> zSetOperations = redisCacheTemplate.opsForZSet();
109 ZSetOperations.TypedTuple<Object> tuple1 = new DefaultTypedTuple<>("v1", 9.6);
110 ZSetOperations.TypedTuple<Object> tuple2 = new DefaultTypedTuple<>("v2", 9.9);
111 Set<ZSetOperations.TypedTuple<Object>> tuples = new HashSet<>();
112 tuples.add(tuple1);
113 tuples.add(tuple2);
114 zSetOperations.add("zkey", tuples);
115 Set<Object> set = zSetOperations.range("zkey", 0, -1);
116 log.info("[对象缓存结果] - {}", set);
117 }
118 }
