RedisTemplate 获取缓存名称 redis缓存查询结果

具体文字说明原理看上面链接的,说的蛮好的,下面我提供完整复制即可正常执行的源码.

//pom文件新增redis坐标
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

//application.yml配置redis相关参数
  redis:
    # Redis服务器地址
    host: 127.0.0.1
    #Redis服务器连接端口
    port: 6379
    #password:
    # Redis数据库索引（默认为0）
    database: 1
    # 连接超时时间（毫秒）
    timeout: 5000
    jedis:
      pool:
        #连接池最大连接数（使用负值表示没有限制）
        max-active: 100
        # 连接池中的最小空闲连接
        max-idle: 10
        # 连接池最大阻塞等待时间（使用负值表示没有限制）
        max-wait: 100000

//新建redisTemplate类
package com.futuredata.cloud.cube.config;


import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.databind.ObjectMapper;
import org.springframework.cache.CacheManager;
import org.springframework.cache.annotation.CachingConfigurerSupport;
import org.springframework.cache.annotation.EnableCaching;
import org.springframework.cache.interceptor.KeyGenerator;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.cache.RedisCacheConfiguration;
import org.springframework.data.redis.cache.RedisCacheManager;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.RedisSerializationContext;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;


import java.lang.reflect.Method;
import java.time.Duration;

/**
 * redis 配置
 */
@Configuration
@EnableCaching
public class RedisConfig extends CachingConfigurerSupport {

    @Override
    @Bean
    public KeyGenerator keyGenerator() {
        return new KeyGenerator() {
            @Override
            public Object generate(Object o, Method method, Object... objects) {
                //格式化缓存key字符串
                StringBuilder sb = new StringBuilder();
                //追加类名
                sb.append(o.getClass().getName());
                //追加方法名
                sb.append(method.getName());
                //遍历参数并且追加
                for (Object obj : objects) {
                    if (obj != null) {
                        sb.append(obj.toString());
                    }
                }
                return sb.toString();
            }
        };
    }

    @Bean
    public CacheManager cacheManager(RedisConnectionFactory factory) {
        RedisSerializer<String> redisSerializer = new StringRedisSerializer();
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);

        //解决查询缓存转换异常的问题
        ObjectMapper om = new ObjectMapper();
        om.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        om.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);
        jackson2JsonRedisSerializer.setObjectMapper(om);

        // 配置序列化（解决乱码的问题）,过期时间120秒
        RedisCacheConfiguration config = RedisCacheConfiguration.defaultCacheConfig()
                .entryTtl(Duration.ofSeconds(86400))
                .serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer))
                .serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(jackson2JsonRedisSerializer))
                .disableCachingNullValues();

        RedisCacheManager cacheManager = RedisCacheManager.builder(factory)
                .cacheDefaults(config)
                .build();
        return cacheManager;
    }

    @Bean
    public RedisTemplate<String, Object> redisTemplate(RedisConnectionFactory connectionFactory) {
        // 创建redisTemplate
        RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
        redisTemplate.setConnectionFactory(connectionFactory);

        // 使用Jackson2JsonRedisSerialize替换默认序列化
        Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);

        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);
        objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL);

        jackson2JsonRedisSerializer.setObjectMapper(objectMapper);

        //set value serializer
        redisTemplate.setDefaultSerializer(jackson2JsonRedisSerializer);
        // key采用String的序列化方式
        redisTemplate.setKeySerializer(new StringRedisSerializer());
        // value序列化方式采用jackson
        redisTemplate.setValueSerializer(jackson2JsonRedisSerializer);
        // hash的key也采用String的序列化方式
        redisTemplate.setHashKeySerializer(new StringRedisSerializer());
        // hash的value序列化方式采用jackson
        redisTemplate.setHashValueSerializer(jackson2JsonRedisSerializer);
        redisTemplate.afterPropertiesSet();
        return redisTemplate;
    }


}

//新建RedisCacheAspect切面类
package com.futuredata.cloud.cube.aspect;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;
import java.util.List;
import java.util.logging.Logger;

@Aspect
@Component
@Slf4j
public class RedisCacheAspect {
//    public static final Logger log = LogUtils.getlogger();
    @Qualifier("redisTemplate")
    @Autowired
    private RedisTemplate rt;


    /**
     * 方法调用前，先查询缓存。如果存在缓存，则返回缓存数据，阻止方法调用;
     * 如果没有缓存，则调用业务方法，然后将结果放到缓存中
     * @param jp
     * @return
     * @throws Throwable
     */
    @Around("execution(* com.futuredata.cloud.cube.mapper.EnvironmentalProtectionFeatureMapper.listSubjectFeatureData(..))")
    public Object cache(ProceedingJoinPoint jp) throws Throwable {
        // 得到类名、方法名和参数
        String clazzName = jp.getTarget().getClass().getName();
        String methodName = jp.getSignature().getName();
        Object[] args = jp.getArgs();

        // 根据类名，方法名和参数生成key
        String key = genKey(clazzName, methodName, args);
        if (log.isDebugEnabled()) {
            log.debug("生成key:{}", key);
        }

        // 得到被代理的方法
        Method me = ((MethodSignature) jp.getSignature()).getMethod();
        // 得到被代理的方法上的注解
//        Class modelType = me.getAnnotation(RedisCache.class).type();
        Class modelType =me.getReturnType();

        // 检查redis中是否有缓存
        String value = (String)rt.opsForHash().get(modelType.getName(), key);

        // result是方法的最终返回结果
        Object result = null;
        if (null == value) {
            // 缓存未命中
            if (log.isDebugEnabled()) {
                log.debug("缓存未命中");
            }

            // 调用数据库查询方法
            result = jp.proceed(args);

            // 序列化查询结果
            String json = serialize(result);

            // 序列化结果放入缓存
            rt.opsForHash().put(modelType.getName(), key, json);
        } else {
            // 缓存命中
            if (log.isDebugEnabled()) {
                log.debug("缓存命中, value = {}", value);
            }

            // 得到被代理方法的返回值类型
            Class returnType = ((MethodSignature) jp.getSignature()).getReturnType();

            // 反序列化从缓存中拿到的json
            result = deserialize(value, returnType);

            if (log.isDebugEnabled()) {
                log.debug("反序列化结果 = {}", result);
            }
        }

        return result;
    }

    /**
     * 在方法调用前清除缓存，然后调用业务方法
     * @param jp
     * @return
     * @throws Throwable
     */
    @Around("execution(* com.futuredata.cloud.cube.mapper.EnvironmentalProtectionFeatureMapper.insert*(..))")
    public Object evictCache(ProceedingJoinPoint jp) throws Throwable {

        // 得到被代理的方法
        Method me = ((MethodSignature) jp.getSignature()).getMethod();
        // 得到被代理的方法上的注解
        Class modelType = me.getAnnotation(RedisEvict.class).type();

        if (log.isDebugEnabled()) {
            log.debug("清空缓存:{}", modelType.getName());
        }

        // 清除对应缓存
        rt.delete(modelType.getName());

        return jp.proceed(jp.getArgs());
    }



    /**
     * 根据类名、方法名和参数生成key
     * @param clazzName
     * @param methodName
     * @param args 方法参数
     * @return
     */
    protected String genKey(String clazzName, String methodName, Object[] args) {
        StringBuilder sb = new StringBuilder(clazzName);
        sb.append("-");
        sb.append(methodName);
        sb.append("-");

        for (Object obj : args) {
            sb.append(obj.toString());
            sb.append("-");
        }

        return sb.toString();
    }

    protected String serialize(Object target) {
        return JSON.toJSONString(target);
    }

    protected Object deserialize(String jsonString, Class clazz) {
        // 序列化结果应该是List对象
        if (clazz.isAssignableFrom(List.class)) {
            return JSONArray.parseArray(jsonString);
        }

        // 序列化结果是普通对象
        return JSON.parseObject(jsonString, clazz);
    }
}