1.引言
我们使用redis作为缓存中间件时，当我们第一次查询数据的时候，是去数据库查询，然后查到的数据封装到实体类中，实体类会被序列化存入缓存中，当第二次查数据时，会直接去缓存中查找被序列化的数据，然后反序列化被我们获取。我们在缓存中看到的序列化数据不直观，如果想看到类似json的数据格式，就需要自定义序列化规则。
2.整合redis
pom.xml:
<!--引入redis-->
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-redis</artifactId>
<version>2.3.0.RELEASE</version>
</dependency>
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
</dependency>
application.yml：
spring: redis: host: 192.168.85.130 port: 6379 database: 0
springboot主配置类要加上@EnableCaching注解
3.自定义序列化
@Configuration
public class MyRedisConfig {
@Bean
public RedisTemplate<Object, Object> empRedisTemplate(RedisConnectionFactory redisConnectionFactory)throws UnknownHostException {
RedisTemplate<Object,Object> template = new RedisTemplate<>();
template.setConnectionFactory(redisConnectionFactory);
Jackson2JsonRedisSerializer<Object> serializer = new Jackson2JsonRedisSerializer<Object>(Object.class);
template.setDefaultSerializer(serializer);
return template;
}
@Bean
public CacheManager cacheManager(RedisConnectionFactory factory){
RedisCacheConfiguration cacheConfiguration = RedisCacheConfiguration.defaultCacheConfig()
.entryTtl(Duration.ofDays(1))
.disableCachingNullValues()
.serializeKeysWith(RedisSerializationContext.SerializationPair
.fromSerializer(new StringRedisSerializer()))
.serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(new GenericJackson2JsonRedisSerializer()));
return RedisCacheManager.builder(factory).cacheDefaults(cacheConfiguration).build();}
}
4.测试
DeptService：
@Service
public class DeptService {
@Autowired
DepartmentMapper departmentMapper;
@Cacheable(value = "dept")
public Department findById(Integer id){
System.out.println("查询"+id+"号部门");
Department department = departmentMapper.getDeptById(id);
return department;
}
}
EmployeeService：
@Service
public class EmployeeService {
@Autowired
EmployeeMapper employeeMapper;
@Cacheable(value = "emp")
public Employee findById(Integer id){
System.out.println("查询"+id+"号员工");
Employee employee = employeeMapper.getEmpById(id);
return employee;
}
}
@Cacheable(value = “dept”) ：该注解在方法上，方法传入参数默认为key值，方法返回值为value值，注解的参数value = "dept"是缓存的名子
结果：
