# springboot-cache

**Repository Path**: feng_zhang/springboot-cache

## Basic Information

- **Project Name**: springboot-cache
- **Description**: 多级缓存使用。
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 2
- **Created**: 2022-03-25
- **Last Updated**: 2022-03-25

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# springboot-cache

#### 项目介绍
多级缓存使用。

#### 软件架构
redis
ehcache


#### 安装教程

1. ehcache 缓存
```
1) Maven依赖
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-cache</artifactId>
</dependency>
<!-- Ehcache 缓存-->
<dependency>
    <groupId>org.ehcache</groupId>
    <artifactId>ehcache</artifactId>
    <version>3.3.0</version>
</dependency>
2)类配置

3)xml配置
ehcache.xml
<config
        xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'
        xmlns='http://www.ehcache.org/v3'
        xsi:schemaLocation="http://www.ehcache.org/v3 http://www.ehcache.org/schema/ehcache-core.xsd">
    <!-- 持久化路径 -->
    <persistence directory="D:/ehcacheData"/>
 
    <!-- 缓存模版,此处为了显示其用法,也可以不用模版直接在cache中配置与模版参数相同 -->
    <cache-template name="template">
        <key-type>java.lang.String</key-type>
        <value-type>java.lang.String</value-type>
        <expiry>
            <!-- 单位默认为秒当用秒作单位时,可以不填-->
            <ttl unit="hours">1</ttl>
        </expiry>
        <resources>
            <!-- 单位默认为entries当用entries作单位时,可以不填-->
            <heap>1</heap>
            <offheap unit="MB">1</offheap>
            <!-- persistent 默认为false可以不填-->
            <disk unit="MB">20</disk>
        </resources>
    </cache-template>
 
    <!-- 缓存对象,如果使用了模版会覆盖模版中的内容,使用uses-template=""来引用模版 -->
    <cache alias="defaultCache" uses-template="template">
        <expiry>
            <!--此处会覆盖模版中的(TTL)配置 -->
            <tti>60</tti>
        </expiry>
        <resources>
            <disk unit="MB" persistent="true"> 500</disk>
        </resources>
        <!-- 没有研究这块,暂时先不管
        <eviction-advisor></eviction-advisor>
        -->
    </cache>
</config>

配置类中加载：
System.out.println("[Ehcache配置初始化<开始>]");
// 配置默认缓存属性
cacheManager = CacheManagerBuilder.newCacheManager(new XmlConfiguration(getClass().getResource("/ehcache.xml")));
cacheManager.init();
System.out.println("[Ehcache配置初始化<完成>]");
配置到application.yml中：
spring:
  cache:
    ehcache:
      config: ehcache.xml
4)代码测试
5)注解测试
@Service
public class EhCacheService {
    @Cacheable(value="test")
    public String readCache(){
        System.out.println("是否缓存，如果没有执行，说明缓存了");
        return "1234";
    }

    @CachePut(value="test")
    public String update() {
        //更新缓存，将会改变内容
        System.out.println("缓存更新了");
        return "456";
    }

    @CacheEvict(value="test",allEntries = true)
    public void deleteAll() {
        System.out.println("移除所有缓存");
    }
}

6) 控制器代码
@RestController
@RequestMapping("/ehcache")
public class EhCacheController {
    @Autowired
    public EhCacheService ehCacheService;

    @GetMapping("/read")
    public String readEhCache(){
        return ehCacheService.readCache();
    }

    @GetMapping("/deleteAll")
    public String deleteAll(){
         ehCacheService.deleteAll();
        return  "移除成功";
    }

    @GetMapping("/update")
    public String update(){
        ehCacheService.update();
        return  "更新成功";
    }
}
```
2. 集成Redis
```
1)Maven依赖
<dependency>
<groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
 <!--spring2.0集成redis所需common-pool2-->
<dependency>
     <groupId>org.apache.commons</groupId>
     <artifactId>commons-pool2</artifactId>
     <version>2.4.2</version>
</dependency>
2)配置类
@Configuration
@AutoConfigureAfter(RedisAutoConfiguration.class)
@Slf4j
public class RedisCacheConfiguration {
    /**
     * 缓存模板
     * @param lettuceConnectionFactory
     * @return
     */
    @Bean
    public RedisTemplate<String, Serializable> redisCacheTemplate(LettuceConnectionFactory lettuceConnectionFactory) {
        RedisTemplate<String, Serializable> template = new RedisTemplate<>();
        template.setKeySerializer(new StringRedisSerializer());
        template.setValueSerializer(new GenericJackson2JsonRedisSerializer());
        template.setConnectionFactory(lettuceConnectionFactory);
        return template;
    }

    /**
     * 缓存管理器
     * @param lettuceConnectionFactory
     * @return
     */
    @Bean
    public CacheManager cacheManager(LettuceConnectionFactory lettuceConnectionFactory) {
        RedisCacheManager.RedisCacheManagerBuilder builder = RedisCacheManager.RedisCacheManagerBuilder
                .fromConnectionFactory(lettuceConnectionFactory);
        @SuppressWarnings("serial")
        Set<String> cacheNames = new HashSet<String>() {
            {
                add("codeNameCache");
            }
        };
        builder.initialCacheNames(cacheNames);
        return builder.build();
    }
}
3)配置文件
spring.redis.host=127.0.0.1
spring.redis.port=6379
spring.redis.password=
# 连接超时时间（毫秒）
spring.redis.timeout=10000
# Redis默认情况下有16个分片，这里配置具体使用的分片
spring.redis.database=0
# 连接池最大连接数（使用负值表示没有限制） 默认 8
spring.redis.lettuce.pool.max-active=8
# 连接池最大阻塞等待时间（使用负值表示没有限制） 默认 -1
spring.redis.lettuce.pool.max-wait=-1
# 连接池中的最大空闲连接 默认 8
spring.redis.lettuce.pool.max-idle=8
# 连接池中的最小空闲连接 默认 0
spring.redis.lettuce.pool.min-idle=0
4)测试类
// TODO 测试线程安全
ExecutorService executorService = Executors.newFixedThreadPool(1000);
IntStream.range(0, 1000).forEach(i ->
        executorService.execute(() -> stringRedisTemplate.opsForValue().increment("kk", 1))
);
stringRedisTemplate.opsForValue().set("k1", "v1");
final String k1 = stringRedisTemplate.opsForValue().get("k1");
log.info("[字符缓存结果] - [{}]", k1);
// TODO Redis支持的命令它都支持
String key = "battcn:user:1";
redisCacheTemplate.opsForValue().set(key, new User(1L, "u1", "pa"));
// TODO 对应 String（字符串）
final User user = (User) redisCacheTemplate.opsForValue().get(key);
log.info("[对象缓存结果] - [{}]", user);
}
```

3. 多级缓存整合
```
1)消息类
@Data
public class CacheMessage implements Serializable {
    private static final long serialVersionUID = 5987219310442078193L;
    private String cacheName;
    private Object key;
    private Integer sender;
    public CacheMessage(String cacheName, Object key) {
        super();
        this.cacheName = cacheName;
        this.key = key;
    }
    public CacheMessage(String cacheName, Object key, Integer sender) {
        super();
        this.cacheName = cacheName;
        this.key = key;
        this.sender = sender;
    }
}
2)自定义缓存类
@Slf4j
public class RedisEhcacheCache extends AbstractValueAdaptingCache {
    private String name;
    private RedisTemplate<Object, Object> redisTemplate;
    private Cache<Object, Object> ehcacheCache;
    private String cachePrefix;
    private long defaultExpiration = 0;
    private Map<String, Long> expires;
    private String topic = "cache:redis:ehcache:topic";
    protected RedisEhcacheCache(boolean allowNullValues) {
        super(allowNullValues);
    }

    public RedisEhcacheCache(String name, RedisTemplate<Object, Object> redisTemplate, Cache<Object, Object> ehcacheCache, RedisEhcacheProperties redisEhcacheProperties) {
        super(redisEhcacheProperties.isCacheNullValues());
        this.name = name;
        this.redisTemplate = redisTemplate;
        this.ehcacheCache = ehcacheCache;
        this.cachePrefix = redisEhcacheProperties.getCachePrefix();
        this.defaultExpiration = redisEhcacheProperties.getRedis().getDefaultExpiration();
        this.expires = redisEhcacheProperties.getRedis().getExpires();
        this.topic = redisEhcacheProperties.getRedis().getTopic();
        log.info("自定义缓存器"+name);
    }

    @Override
    public String getName() {
        return this.name;
    }

    @Override
    public Object getNativeCache() {
        return this;
    }

    @SuppressWarnings("unchecked")
    @Override
    public <T> T get(Object key, Callable<T> valueLoader) {
        log.info("调用自定义缓存GET方法");
        Object value = lookup(key);
        if(value != null) {
            return (T) value;
        }
        ReentrantLock lock = new ReentrantLock();
        try {
            lock.lock();
            value = lookup(key);
            if(value != null) {
                return (T) value;
            }
            value = valueLoader.call();
            Object storeValue = toStoreValue(valueLoader.call());
            put(key, storeValue);
            return (T) value;
        } catch (Exception e) {
            try {
                Class<?> c = Class.forName("org.springframework.cache.Cache$ValueRetrievalException");
                Constructor<?> constructor = c.getConstructor(Object.class, Callable.class, Throwable.class);
                RuntimeException exception = (RuntimeException) constructor.newInstance(key, valueLoader, e.getCause());
                throw exception;
            } catch (Exception e1) {
                throw new IllegalStateException(e1);
            }
        } finally {
            lock.unlock();
        }
    }

    //从持久层读取value，然后存入缓存。允许value = null
    @Override
    public void put(Object key, Object value) {
        log.info("调用自定义缓存PUT方法"+getKey(key));
        if (!super.isAllowNullValues() && value == null) {
            this.evict(key);
            return;
        }
        long expire = getExpire();
        if(expire > 0) {
            redisTemplate.opsForValue().set(getKey(key), toStoreValue(value), expire, TimeUnit.MILLISECONDS);
        } else {
            redisTemplate.opsForValue().set(getKey(key), toStoreValue(value));
        }

        //通过redis推送消息，使其他服务的ehcache失效。
        //原来的有个缺点：服务1给缓存put完KV后推送给redis的消息，服务1本身也会接收到该消息，
        // 然后会将刚刚put的KV删除。这里把ehcacheCache的hashcode传过去，避免这个问题。
        push(new CacheMessage(this.name, key, this.ehcacheCache.hashCode()));
        ehcacheCache.put(key, value);
    }
    //key的生成    name:cachePrefix:key
    private Object getKey(Object key) {
        log.info("调用自定义缓存getKey方法");
        return this.name.concat(":").concat(StringUtils.isEmpty(cachePrefix) ? key.toString() : cachePrefix.concat(":").concat(key.toString()));
    }

    private long getExpire() {
        log.info("调用自定义缓存getExpire方法");
        long expire = defaultExpiration;
        Long cacheNameExpire = expires.get(this.name);
        return cacheNameExpire == null ? expire : cacheNameExpire.longValue();
    }

    @Override
    public ValueWrapper putIfAbsent(Object key, Object value) {
        Object cacheKey = getKey(key);
        Object prevValue = null;
        // 考虑使用分布式锁，或者将redis的setIfAbsent改为原子性操作
        synchronized (key) {
            prevValue = redisTemplate.opsForValue().get(cacheKey);
            if(prevValue == null) {
                long expire = getExpire();
                if(expire > 0) {
                    redisTemplate.opsForValue().set(getKey(key), toStoreValue(value), expire, TimeUnit.MILLISECONDS);
                } else {
                    redisTemplate.opsForValue().set(getKey(key), toStoreValue(value));
                }
                //
                push(new CacheMessage(this.name, key, this.ehcacheCache.hashCode()));
                //
                ehcacheCache.put(key, toStoreValue(value));
            }
        }
        return toValueWrapper(prevValue);
    }

    @Override
    public void evict(Object key) {
        log.info("调用自定义缓存evict方法");
        // 先清除redis中缓存数据，然后清除ehcache中的缓存，避免短时间内如果先清除ehcache缓存后其他请求会再从redis里加载到ehcache中
        redisTemplate.delete(getKey(key));
        push(new CacheMessage(this.name, key, this.ehcacheCache.hashCode()));
        //
        ehcacheCache.remove(key);
    }

    @Override
    public void clear() {
        // 先清除redis中缓存数据，然后清除ehcache中的缓存，避免短时间内如果先清除ehcache缓存后其他请求会再从redis里加载到ehcache中
        Set<Object> keys = redisTemplate.keys(this.name.concat(":"));
        for(Object key : keys) {
            redisTemplate.delete(key);
        }
        push(new CacheMessage(this.name, null));
        ehcacheCache.clear();
    }

    //获根据key取缓存,如果返回null，则要读取持久层
    @Override
    protected Object lookup(Object key) {
        Object cacheKey = getKey(key);
        Object value = ehcacheCache.get(key);
        if(value != null) {
            log.info("获取ehcache缓存, 这个键为 : {}", cacheKey);
            return value;
        }
        value = redisTemplate.opsForValue().get(cacheKey);
        log.info("值："+value);
        log.info("键："+cacheKey);
        if(value != null) {
            log.info("获取redis缓存并添加到ehcache, 这个键为: {}", cacheKey);
            //将二级缓存重新复制到一级缓存。原理是最近访问的key很可能再次被访问
            ehcacheCache.put(cacheKey, value);
        }
        return value;
    }

    /**
     * 缓存变更时，利用redis的消息订阅功能，通知其他节点清理本地缓存。
     * @description
     * @param message
     */
    private void push(CacheMessage message) {
        redisTemplate.convertAndSend(topic, message);
    }

    /**
     * @description 清理本地缓存
     * @param key
     */
    public void clearLocal(Object key) {
        log.info("清理本地缓存, 这个键为 : {}", key);
        if(key == null) {
            ehcacheCache.clear();
        } else {
            ehcacheCache.remove(key);
        }
    }
    public Cache<Object, Object> getLocalCache(){
        return ehcacheCache;
    }
}
3)监听redis消息类
@Slf4j
public class CacheMessageListener implements MessageListener {
    private RedisTemplate<Object, Object> redisTemplate;
    private RedisEhcacheCacheManager redisEhcacheCacheManager;
    public CacheMessageListener(RedisTemplate<Object, Object> redisTemplate,
                                RedisEhcacheCacheManager redisEhcacheCacheManager) {
        super();
        this.redisTemplate = redisTemplate;
        this.redisEhcacheCacheManager = redisEhcacheCacheManager;
        log.info("2、缓存监听");
    }

    @Override
    public void onMessage(Message message, byte[] pattern) {
        CacheMessage cacheMessage = (CacheMessage) redisTemplate.getValueSerializer().deserialize(message.getBody());
        log.info("接受redis消息, 缓存名为： {}, 这个键为： {}", cacheMessage.getCacheName(), cacheMessage.getKey());
        //清除ehcache缓存
        redisEhcacheCacheManager.clearLocal(cacheMessage.getCacheName(), cacheMessage.getKey(), cacheMessage.getSender());
    }
}
4)自定义缓存管理类
@Slf4j
public class RedisEhcacheCacheManager implements CacheManager {
    private ConcurrentMap<String, Cache> cacheMap = new ConcurrentHashMap<String, Cache>();
    private RedisEhcacheProperties redisEhcacheProperties;
    private RedisTemplate<Object, Object> redisTemplate;
    private boolean dynamic = true;
    private Set<String> cacheNames;
    private org.ehcache.CacheManager ehCacheManager;
    private CacheConfiguration configuration;

    public RedisEhcacheCacheManager(RedisEhcacheProperties redisEhcacheProperties,
                                    RedisTemplate<Object, Object> redisTemplate) {
        super();
        this.redisEhcacheProperties = redisEhcacheProperties;
        this.redisTemplate = redisTemplate;
        this.dynamic = redisEhcacheProperties.isDynamic();
        this.cacheNames = redisEhcacheProperties.getCacheNames();
        setAboutEhCache();
    }

    /**
     * 设置EhCache缓存
     */
    private void setAboutEhCache(){
        long ehcacheExpire = redisEhcacheProperties.getEhcache().getExpireAfterWrite();
        this.configuration =
                CacheConfigurationBuilder
                        .newCacheConfigurationBuilder(Object.class, Object.class, ResourcePoolsBuilder.heap(redisEhcacheProperties.getEhcache().getMaxEntry()))
                        .withExpiry(ExpiryPolicyBuilder.timeToLiveExpiration(Duration.ofSeconds(ehcacheExpire)))
                        .build();
        this.ehCacheManager = CacheManagerBuilder
                .newCacheManagerBuilder()
                .build();
        this.ehCacheManager.init();
        log.info("1、设置缓存");
    }

    /**
     * 获取缓存
     * @param name
     * @return
     */
    @Override
    public Cache getCache(String name) {
        Cache cache = cacheMap.get(name);
        if(cache != null) {
            return cache;
        }
        if(!dynamic && !cacheNames.contains(name)) {
            return cache;
        }
        cache = new RedisEhcacheCache(name, redisTemplate, getEhcache(name), redisEhcacheProperties);
        Cache oldCache = cacheMap.putIfAbsent(name, cache);
        log.debug("创建缓存实例, 缓存名字为 : {}", name);
        return oldCache == null ? cache : oldCache;
    }

    /**
     * 获取Ehcache 缓存
     * @param name
     * @return
     */
    public org.ehcache.Cache<Object, Object> getEhcache(String name){
        org.ehcache.Cache<Object, Object> res = ehCacheManager.getCache(name, Object.class, Object.class);
        if(res != null){
            return res;
        }
        return ehCacheManager.createCache(name, configuration);
    }

    @Override
    public Collection<String> getCacheNames() {
        return this.cacheNames;
    }

    public void clearLocal(String cacheName, Object key, Integer sender) {
        Cache cache = cacheMap.get(cacheName);
        if(cache == null) {
            return ;
        }
        RedisEhcacheCache redisEhcacheCache = (RedisEhcacheCache) cache;
        //如果是发送者本身发送的消息，就不进行key的清除
        if(redisEhcacheCache.getLocalCache().hashCode() != sender) {
            redisEhcacheCache.clearLocal(key);
        }
    }
}
5)缓存配置类CacheRedisEhcacheAutoConfiguration
@Configuration
@AutoConfigureAfter(RedisAutoConfiguration.class)
//二级缓存和一级缓存切换:true 启用二级缓存，false禁用二级缓存
@ConditionalOnProperty(name = "cache.use2L", havingValue = "true", matchIfMissing = false)
@EnableConfigurationProperties(RedisEhcacheProperties.class)
@Slf4j
public class CacheRedisEhcacheAutoConfiguration {

    @Autowired
    private RedisEhcacheProperties redisEhcacheProperties;

    /**
     * Redis+Ehcache缓存管理
     * @param redisTemplate
     * @return
     */
    @Bean
    public RedisEhcacheCacheManager cacheManager(RedisTemplate<Object, Object> redisTemplate) {
        return new RedisEhcacheCacheManager(redisEhcacheProperties, redisTemplate);
    }

    /**
     * RedisMessage 监听
     * @param redisTemplate
     * @param redisEhcacheCacheManager
     * @return
     */
    @Bean
    @ConditionalOnBean(RedisEhcacheCacheManager.class)
    public RedisMessageListenerContainer redisMessageListenerContainer(RedisTemplate<Object, Object> redisTemplate,
                                                                       RedisEhcacheCacheManager redisEhcacheCacheManager) {
        RedisMessageListenerContainer redisMessageListenerContainer = new RedisMessageListenerContainer();
        redisMessageListenerContainer.setConnectionFactory(redisTemplate.getConnectionFactory());
        CacheMessageListener cacheMessageListener = new CacheMessageListener(redisTemplate, redisEhcacheCacheManager);
       //添加缓存监听器
        log.info("3、添加缓存监听到Redis");
        redisMessageListenerContainer.addMessageListener(cacheMessageListener, new ChannelTopic(redisEhcacheProperties.getRedis().getTopic()));
        return redisMessageListenerContainer;
    }
}
6)Redis配置类RedisCacheConfig
@Configuration
@EnableCaching//开启注解
@ConditionalOnProperty(name = "cache.use2L", havingValue = "false", matchIfMissing = true)
@EnableConfigurationProperties(RedisEhcacheProperties.class)
@Slf4j
public class RedisCacheConfig {
    /**
     * 缓存模板
     *
     * @param lettuceConnectionFactory
     * @return
     */
    @Bean
    public RedisTemplate<String, Serializable> redisCacheTemplate(LettuceConnectionFactory lettuceConnectionFactory) {
        RedisTemplate<String, Serializable> template = new RedisTemplate<>();
        template.setKeySerializer(new StringRedisSerializer());
        template.setValueSerializer(new GenericJackson2JsonRedisSerializer());
        template.setConnectionFactory(lettuceConnectionFactory);
        return template;
    }

    /**
     * 缓存管理器
     *
     * @param lettuceConnectionFactory
     * @return
     */
    @Bean
    public CacheManager cacheManager(LettuceConnectionFactory lettuceConnectionFactory) {
        RedisCacheManager.RedisCacheManagerBuilder builder = RedisCacheManager.RedisCacheManagerBuilder
                .fromConnectionFactory(lettuceConnectionFactory);
        return builder.build();
    }
}
7)EhCache配置文件
<?xml version="1.0" encoding="UTF-8"?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd"
         updateCheck="false" name="ec">

    <diskStore path="java.io.tmpdir"/> <!-- 缓存存放目录(此目录为放入系统默认缓存目录),也可以是”D:/cache“ java.io.tmpdir -->
    <defaultCache
            maxElementsInMemory="10000"
            eternal="false"
            timeToIdleSeconds="120"
            timeToLiveSeconds="120"
            overflowToDisk="true"
            maxElementsOnDisk="10000000"
            diskPersistent="false"
            diskExpiryThreadIntervalSeconds="120"
            memoryStoreEvictionPolicy="LRU"
    />

    <!--  -->
    <cache name="j2CacheRedis"
           maxElementsInMemory="1000"
           eternal="false"
           timeToIdleSeconds="120"
           timeToLiveSeconds="140"
           overflowToDisk="false"
           memoryStoreEvictionPolicy="LRU"/>

    <!--
  name：Cache的唯一标识
  maxElementsInMemory：内存中最大缓存对象数
  maxElementsOnDisk：磁盘中最大缓存对象数，若是0表示无穷大
  eternal：Element是否永久有效，一但设置了，timeout将不起作用
  overflowToDisk：配置此属性，当内存中Element数量达到maxElementsInMemory时，Ehcache将会Element写到磁盘中
  timeToIdleSeconds：设置Element在失效前的允许闲置时间。仅当element不是永久有效时使用，可选属性，默认值是0，也就是可闲置时间无穷大
  timeToLiveSeconds：设置Element在失效前允许存活时间。最大时间介于创建时间和失效时间之间。仅当element不是永久有效时使用，默认是0.，也就是element存活时间无穷大
  diskPersistent：是否缓存虚拟机重启期数据
  diskExpiryThreadIntervalSeconds：磁盘失效线程运行时间间隔，默认是120秒
  diskSpoolBufferSizeMB：这个参数设置DiskStore（磁盘缓存）的缓存区大小。默认是30MB。每个Cache都应该有自己的一个缓冲区
   memoryStoreEvictionPolicy：当达到maxElementsInMemory限制时，Ehcache将会根据指定的策略去清理内存。默认策略是LRU（最近最少使用）。你可以设置为FIFO（先进先出）或是LFU（较少使用）
  -->
</ehcache>
8)属性配置文件
spring.redis.hostName=127.0.0.1
spring.redis.port=6379
spring.redis.timeOut=1000
spring.redis.maxIdle=10
spring.redis.maxWaitMillis=15000
spring.redis.testOnBorrow=true
spring.redis.testWhileIdle=false

## redis-starter的配置
spring.cache.cache-names=cache1,cache2,cache3
spring.redis.timeout=10000
#自定义配置。expire统一单位为毫秒
cache.multi.cacheNames=cache1,cache2,cache3
cache.multi.ehcache.expireAfterWrite=5000
cache.multi.ehcache.maxEntry=1000
cache.multi.redis.defaultExpiration=60000
cache.multi.redis.expires.cache1=50000
cache.multi.redis.expires.cache2=70000
cache.multi.redis.expires.cache3=70000
#开启二级缓存
cache.use2L=true
9)测试
@Component
@Slf4j
public class CacheTestService {
    //cacheManager = "cacheManager"可以不指定
    @Cacheable(value = "gerritCache", key = "#root.targetClass + '_' + #root.methodName + '_' + #root.args[0]", cacheManager = "cacheManager")
    public String get(long id) {
        log.info("获取数据库数据");
        return "test";
    }
}

public class CacheTestServiceTest extends SpringbootCacheApplicationTests {
    @Autowired
    private  CacheTestService cacheTestService;
    @Test
    public void get0() throws Exception {
        cacheTestService.get(123L);
    }
}

说明：
如果cache.use2L=true设置为true
将开启Ehcache缓存，如果设置为false则为只使用Redsi缓存。

```

#### 使用说明

1. xxxx
2. xxxx
3. xxxx