目录

配置自定义RedisTemplate 

引入依赖

配置连接redis

编写测试类

出现问题

配置序列化

解决redis序列化java8 LocalDateTime

问题背景

问题描述

问题分析

解决方案一（全局）

解决方案二（单个字段）

配置自定义RedisTemplate 

引入依赖

<!-- redis -->
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-data-redis -->
<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-redis</artifactId>
  <version>2.6.4</version>
</dependency>

配置连接redis

spring:
  redis: #配置redis连接
    host: 192.168.88.188
    port: 6379
    database: 0

编写测试类

然后就是写一个测试类，测一下Redis引入之后是否能过正常使用。新建文件RedisTest.java.

@RunWith(SpringRunner.class)
@SpringBootTest("com.jiamian.xxxxx")
public class RedisTest {

    @Resource
    RedisTemplate redisTemplate;

    @Test
    public void test(){
        //操作string类型的 操作对象
        ValueOperations valueOperations = redisTemplate.opsForValue();
        //增
        valueOperations.set("jiamian_string","str123");
        valueOperations.set("jiamian_Integer",1);
        valueOperations.set("jiamian_Double",2.0);
        User user = new User();
        user.setId(0L);
        user.setUsername("加棉");
        valueOperations.set("jiamian_User",user);

        //查
        Object jiamian_string = valueOperations.get("jiamian_string");
        Object jiamian_Integer = valueOperations.get("jiamian_Integer");
        Object jiamian_Double = valueOperations.get("jiamian_Double");
        Object jiamian_User = valueOperations.get("jiamian_User");
        System.out.println(jiamian_string);
        System.out.println(jiamian_Integer);
        System.out.println(jiamian_Double);
        System.out.println(jiamian_User);
    }
}

出现问题

去redis-cli客户端中查看发现存入的key和我们想象中的不同，这里的序列编码有问题。这是因为RedisTemplate默认使用了jdk序列化器。

如果操作的key和value都是string类型，可以使用StringRedisTemplate进行操作。

StringTemplate部分源码如下:

配置序列化

因为我们这里存的值有多种类型，我们就使用自定义的序列化器

@Configuration
public class RedisTemplateConfig {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
        //创建RedisTemplate对象
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
       //设置连接工厂
        redisTemplate.setConnectionFactory(connectionFactory);
        //设置Key的序列化
        redisTemplate.setKeySerializer(RedisSerializer.string());

        //创建Json序列化工具
        GenericJackson2JsonRedisSerializer jsonRedisSerializer = new GenericJackson2JsonRedisSerializer();
        //设置Value的序列化
        redisTemplate.setValueSerializer(jsonRedisSerializer);

        return redisTemplate;
    }
}

在QuickRedis中查看,问题解决!!!

后续会出现的问题:
如何实体类中有LocalDateTime类型的属性,在redis序列化时会报以下错误.
Redis序列化 jdk8  LocalDateTime问题

org.springframework.data.redis.serializer.SerializationException: Could not write JSON: Java 8 date/time type `java.time.LocalDateTime` not supported by default: add Module "com.fasterxml.jackson.datatype:jackson-datatype-jsr310" to enable handling

解决redis序列化java8 LocalDateTime

问题背景

目前项目全面支持JDK1.8，使用 LocalDateTime 代替 Date,原因为 date 格式化时不安全。

问题描述

org.springframework.data.redis.serializer.SerializationException: Could not write JSON: Java 8 date/time type `java.time.LocalDateTime` not supported by default: add Module "com.fasterxml.jackson.datatype:jackson-datatype-jsr310" to enable handling

GenericJackson2JsonRedisSerializer 解析 出错

解决方案一（全局）

<dependency>
    <groupId>com.fasterxml.jackson.datatype</groupId>
    <artifactId>jackson-datatype-jsr310</artifactId>
    <version>2.14.2</version>
</dependency>

/**
 * 自定义序列化
 */
@Configuration
public class RedisTemplateConfig {

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<String, Object>();
        redisTemplate.setConnectionFactory(connectionFactory);
        // key采用String的序列化方式
        redisTemplate.setKeySerializer(RedisSerializer.string());
        // hash的key也采用String的序列化方式
        redisTemplate.setHashKeySerializer(RedisSerializer.string());



        //创建Json序列化工具  ,支持jdk8 LocalDateTime
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);

        //LocalDatetime序列化
        JavaTimeModule timeModule = new JavaTimeModule();
        timeModule.addDeserializer(LocalDate.class,
                new LocalDateDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
        timeModule.addDeserializer(LocalDateTime.class,
                new LocalDateTimeDeserializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));
        timeModule.addSerializer(LocalDate.class,
                new LocalDateSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd")));
        timeModule.addSerializer(LocalDateTime.class,
                new LocalDateTimeSerializer(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")));

        om.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);
        om.registerModule(timeModule);
        jackson2JsonRedisSerializer.setObjectMapper(om);

        // value序列化方式采用jackson
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
        // hash的value序列化方式采用jackson
        redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }
}

@JsonDeserialize(using = LocalDateTimeDeserializer.class)
@JsonSerialize(using = LocalDateTimeSerializer.class)
protected LocalDateTime createTime;