本文主要是介绍SpringBoot集成Ehcache、Redis示例,希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!
一、摘要
1.1、Spring3.1开始内置了五个缓存管理器实现,如下所示:
- SimpleCacheManager
- NoOpCacheManager
- ConcurrentMapCacheManager
- CompositeCacheManager
- EhcacheCacheManager
1.2、Spring3.2引入了另外一个缓存管理器,这个管理器可以用在基于Jcache(JSR-107)的缓存供应商之中。除了核心的spring框架,spring data又提供了两个缓存管理器。
- RedisCacheManager
- GemfireCacheManager
JSR是Java Specification Requests的缩写,意思是Java 规范提案。是指向JCP(Java Community Process)提出新增一个标准化技术规范的正式请求。任何人都可以提交JSR,以向Java平台增添新的API和服务。JSR已成为Java界的一个重要标准。
今天我们要讲的是Srping目前集成使用比较广泛的Ehcache和Redis集成方式。
二、集成Ehcache
主要依赖包是spring-boot-starter-cache和ehcache,如下:
<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.6.0</version><relativePath/></parent><groupId>com.example</groupId><artifactId>spring-cache</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-cache</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><spring-cloud.version>2021.0.0-RC1</spring-cloud.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter</artifactId></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- mybatis plus 代码生成器 --><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.2.0</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.71</version></dependency><!--spring的集成缓存框架的jar--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-cache</artifactId></dependency><!--spring要集成的ehcache缓存jar--><dependency><groupId>net.sf.ehcache</groupId><artifactId>ehcache</artifactId></dependency></dependencies>
resources目录下配置ehcache.xml配置文件():
<?xml version="1.0" encoding="UTF-8" ?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xsi:noNamespaceSchemaLocation="../../../../../../ehcache.xsd"><!-- 磁盘缓存位置 --><diskStore path="java.io.tmpdir"/><!--defaultCache:echcache 的默认缓存策略 -->
<!-- <defaultCache-->
<!-- maxElementsInMemory="10000"-->
<!-- eternal="false"-->
<!-- timeToIdleSeconds="300"-->
<!-- timeToLiveSeconds="300"-->
<!-- maxElementsOnDisk="10000000"-->
<!-- diskExpiryThreadIntervalSeconds="300"-->
<!-- memoryStoreEvictionPolicy="LRU">-->
<!-- <persistence strategy="localTempSwap"/>-->
<!-- </defaultCache>--><!-- 根据id查询博客方法 --><cache name="blog:queryById"maxElementsInMemory="30"eternal="false"timeToIdleSeconds="30"timeToLiveSeconds="30"maxElementsOnDisk="10000000"diskExpiryThreadIntervalSeconds="300"memoryStoreEvictionPolicy="LRU"><persistence strategy="localTempSwap"/></cache></ehcache>
ehcache属性注解:
1、name:缓存名称。
2、maxElementsInMemory:缓存最大个数。
3、eternal:对象是否永久有效,一但设置了,timeout将不起作用。
4、timeToIdleSeconds:设置对象在失效前的允许闲置时间(单位:秒)。仅当eternal=false对象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。
5、timeToLiveSeconds:设置对象在失效前允许存活时间(单位:秒)。最大时间介于创建时间和失效时间之间。仅当eternal=false对象不是永久有效时使用,默认是0.,也就是对象存活时间无穷大。
6、overflowToDisk:当内存中对象数量达到maxElementsInMemory时,Ehcache将会对象写到磁盘中。
7、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。
8、maxElementsOnDisk:硬盘最大缓存个数。
9、diskPersistent:是否缓存虚拟机重启期数据(Whether the disk store persists between restarts of the Virtual Machine. The default value is false.
10、diskExpiryThreadIntervalSeconds:磁盘失效线程运行时间间隔,默认是120秒。
11、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)。
12、clearOnFlush:内存数量最大时是否清除。
ehcache管理器的实现:
@Component
public class EhCacheManager {/*** ehcache缓存管理器* @return*/@Bean(name = "ehCacheCacheManager")EhCacheCacheManager cacheManager() {EhCacheCacheManager cacheManager = new EhCacheCacheManager();//设置事物失败回滚(如果失败,缓存也会回滚)cacheManager.setTransactionAware(Boolean.TRUE);return cacheManager;}}
application.yml关键配置:
# 关联Ehcache的配置文件
spring:cache:ehcache:config: classpath:ehcache.xmltype: ehcache
三、集成Redis
主要依赖包是spring-boot-starter-cache和spring-boot-starter-data-redis,如下:
<parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.6.0</version><relativePath/></parent><groupId>com.example</groupId><artifactId>spring-cache</artifactId><version>0.0.1-SNAPSHOT</version><name>spring-cache</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version><spring-cloud.version>2021.0.0-RC1</spring-cloud.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.cloud</groupId><artifactId>spring-cloud-starter</artifactId></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- mybatis plus 代码生成器 --><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.2.0</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>fastjson</artifactId><version>1.2.71</version></dependency><!--spring的集成缓存框架的jar--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-cache</artifactId></dependency><!--spring要集成的redis缓存jar--><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-redis</artifactId></dependency></dependencies>
注意点:原生的spring cache不支持缓存过期,默认都是没有过期时间的,需要自定义缓存过期时间,所以cache管理器有点特殊。
redisCache管理器的实现:
@Slf4j
@Configuration
public class CustomizerRedisCacheManager {@Value("${redis.cache.initialCacheNamesAndDuration}")private String[] initialCacheNames;//分隔符private static final String SEPARATOR = "#";//有效时间的正则表达式private Pattern pattern = Pattern.compile("(?:([-+]?[0-9]+)H)|(?:([-+]?[0-9]+)M)|(?:([-+]?[0-9]+)S)", Pattern.CASE_INSENSITIVE);@Bean(name = "redisCacheManager")@Primary //自动装配时当出现多个Bean候选者时,被注解为@Primary的Bean将作为首选者public RedisCacheManager cacheManager(RedisConnectionFactory redisConnectionFactory) {RedisCacheWriter redisCacheWriter = RedisCacheWriter.nonLockingRedisCacheWriter(redisConnectionFactory);RedisSerializer<String> redisSerializer = new StringRedisSerializer();Map<String, RedisCacheConfiguration> initialCacheConfigurations = new LinkedHashMap();for (String initialCacheName : initialCacheNames) {String cacheName = initialCacheName.substring(0, initialCacheName.indexOf(SEPARATOR));String durationStr = initialCacheName.substring(initialCacheName.lastIndexOf(SEPARATOR) + 1);Duration duration;try {duration = parseDuration(durationStr);} catch (Exception e) {log.error(e.getMessage());continue;}// redis配置缓存key的有效时间、key的序列化器、value的序列化器RedisCacheConfiguration cacheConfiguration = RedisCacheConfiguration.defaultCacheConfig().entryTtl(duration) //设置缓存key有效时间.serializeKeysWith(RedisSerializationContext.SerializationPair.fromSerializer(redisSerializer)).serializeValuesWith(RedisSerializationContext.SerializationPair.fromSerializer(getJackson2JsonRedisSerializer())).disableCachingNullValues();initialCacheConfigurations.put(cacheName, cacheConfiguration);}RedisCacheManager cacheManager = RedisCacheManager.builder(redisCacheWriter).withInitialCacheConfigurations(initialCacheConfigurations).build();return cacheManager;}/*** 解析时间单位字符串* @param duration* @return*/private Duration parseDuration(@Nullable String duration) {Matcher matcher = pattern.matcher(duration);if(! matcher.matches()){throw new RuntimeException("过期时间格式是冒号后面数字跟H/M/S.");}if(duration.endsWith("H")){return Duration.ofHours(Long.valueOf(duration.replace("H", "")));}if(duration.endsWith("M")){return Duration.ofHours(Long.valueOf(duration.replace("M", "")));}if(duration.endsWith("S")){return Duration.ofHours(Long.valueOf(duration.replace("S", "")));}else{throw new RuntimeException("未识别的有效时间单位:" + duration);}}public RedisSerializer getJackson2JsonRedisSerializer(){Jackson2JsonRedisSerializer jackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer(Object.class);ObjectMapper objectMapper = new ObjectMapper();//反序列化时智能识别变量名(识别没有按驼峰格式命名的变量名)objectMapper.setVisibility(PropertyAccessor.ALL, JsonAutoDetect.Visibility.ANY);//反序列化识别对象类型//objectMapper.enableDefaultTyping(ObjectMapper.DefaultTyping.NON_FINAL); 该方法已废弃,使用activateDefaultTyping(...)代替objectMapper.activateDefaultTyping(LaissezFaireSubTypeValidator.instance ,ObjectMapper.DefaultTyping.NON_FINAL, JsonTypeInfo.As.PROPERTY);//反序列化如果未识别的属性,不抛出异常objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);//反序列化如果碰到不识别的枚举值,是否作为空值解释,true:不会抛不识别的异常, 会赋空值,false:会抛不识别的异常objectMapper.configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL, true);jackson2JsonRedisSerializer.setObjectMapper(objectMapper);return jackson2JsonRedisSerializer;}
}
application.yml的关键配置:
#redis缓存key的有效时间配置
redis:cache:initialCacheNamesAndDuration: blog:queryById#10S#redis配置
spring:redis:host: localhostport: 6379database: 0
参考文章:
1、https://segmentfault.com/a/1190000022548904
2、springboot使用cache集成redis(自定义每个key过期时间)_JGMa_TiMo的博客-CSDN博客
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