Spring4.1新特性——Spring緩存框架加強(轉)

時間 2019-11-20

標籤 spring4.1 spring 特性緩存框架加強欄目 Spring 简体版

原文原文鏈接

目錄java

Spring4.1新特性——綜述git

Spring4.1新特性——Spring核心部分及其餘github

Spring4.1新特性——Spring緩存框架加強spring

Spring4.1新特性——異步調用和事件機制的異常處理數據庫

Spring4.1新特性——數據庫集成測試腳本初始化api

Spring4.1新特性——Spring MVC加強緩存

Spring4.1新特性——頁面自動化測試框架Spring MVC Test HtmlUnit簡介框架

Spring4.1新特性——靜態資源處理加強異步

Spring 4.1提供了對jcache的支持，並對cache抽象部分進行了一些簡單的加強。在集成jcache時是很是費勁的，版本之間各類不兼容，不建議用於正式環境，在正式環境中可使用如Guava Cache或Ehcache。ide

jcache依賴：

Java代碼

<dependency>
<groupId>net.sf.ehcache</groupId>
<artifactId>ehcache-jcache</artifactId>
<version>${ehcache-jcache.version}</version>
</dependency>
<dependency>
<groupId>javax.cache</groupId>
<artifactId>cache-api</artifactId>
<version>${javax.cache.version}</version>
</dependency>
<dependency>
<groupId>org.jsr107.ri</groupId>
<artifactId>cache-ri-impl</artifactId>
<version>${cache-ri-impl.version}</version>
</dependency>

<javax.cache.version>1.0.0</javax.cache.version>、<cache-ri-impl.version>1.0.0</cache-ri-impl.version>、<ehcache-jcache.version>1.2</ehcache-jcache.version>，具體請參考源碼。

一、Jcache集成

建立Cache：

Java代碼

javax.cache.CacheManager cacheManager = Caching.getCachingProvider().getCacheManager();
MutableConfiguration<Object, Object> mutableConfiguration = new MutableConfiguration<Object, Object>();
mutableConfiguration.setStoreByValue(false); // otherwise value has to be Serializable
cacheManager.createCache("user", mutableConfiguration);
cacheManager.createCache("user2", mutableConfiguration);
cacheManager.createCache("user3", mutableConfiguration);
JCacheCacheManager jCacheCacheManager = new JCacheCacheManager(cacheManager);
return jCacheCacheManager;

Java Config方式提供了CachingConfigurer用於提供配置回調：

Java代碼

@Configuration
@ComponentScan(basePackages = "com.sishuok.spring.service")
@EnableCaching(proxyTargetClass = true)
public class AppConfig implements CachingConfigurer {
@Bean
@Override
public CacheManager cacheManager() {
javax.cache.CacheManager cacheManager = Caching.getCachingProvider().getCacheManager();
MutableConfiguration<Object, Object> mutableConfiguration = new MutableConfiguration<Object, Object>();
mutableConfiguration.setStoreByValue(false); // otherwise value has to be Serializable
cacheManager.createCache("user", mutableConfiguration);
cacheManager.createCache("user2", mutableConfiguration);
cacheManager.createCache("user3", mutableConfiguration);
JCacheCacheManager jCacheCacheManager = new JCacheCacheManager(cacheManager);
return jCacheCacheManager;
}
@Bean
@Override
public CacheResolver cacheResolver() {
return new MyCacheResolver();
}
@Bean
@Override
public KeyGenerator keyGenerator() {
return new SimpleKeyGenerator();
}
@Override
public CacheErrorHandler errorHandler() {
return new CacheErrorHandler() {
@Override
public void handleCacheGetError(RuntimeException exception, Cache cache, Object key) {
System.out.println("cache get error");
}
@Override
public void handleCachePutError(RuntimeException exception, Cache cache, Object key, Object value) {
System.out.println("cache put error");
}
@Override
public void handleCacheEvictError(RuntimeException exception, Cache cache, Object key) {
System.out.println("cache evict error");
}
@Override
public void handleCacheClearError(RuntimeException exception, Cache cache) {
System.out.println("cache clear error");
}
};
}
}

二、@CacheConfig指定全局Cache配置

Spring 4.1以前須要每一個方法上都指定：

Java代碼

@Service
public class UserService {
Set<User> users = new HashSet<User>();
@CachePut(value = "user", key = "#user.id")
public User save(User user) {
users.add(user);
return user;
}
@CachePut(value = "user", key = "#user.id")
public User update(User user) {
users.remove(user);
users.add(user);
return user;
}
@CacheEvict(value = "user", key = "#user.id")
public User delete(User user) {
users.remove(user);
return user;
}
@CacheEvict(value = "user", allEntries = true)
public void deleteAll() {
users.clear();
}
@Cacheable(value = "user", key = "#id")
public User findById(final Long id) {
System.out.println("cache miss, invoke find by id, id:" + id);
for (User user : users) {
if (user.getId().equals(id)) {
return user;
}
}
return null;
}
}

Spring 4.1時能夠直接在類級別使用@CacheConfig指定：

Java代碼

@Service
@CacheConfig(cacheNames = {"user", "user2"})
public class UserService {
Set<User> users = new HashSet<User>();
@CachePut(key = "#user.id")
public User save(User user) {
users.add(user);
return user;
}
@CachePut(key = "#user.id")
public User update(User user) {
users.remove(user);
users.add(user);
return user;
}
@CacheEvict(key = "#user.id")
public User delete(User user) {
users.remove(user);
return user;
}
@CacheEvict(allEntries = true)
public void deleteAll() {
users.clear();
}
@Cacheable(key = "#id")
public User findById(final Long id) {
System.out.println("cache miss, invoke find by id, id:" + id);
for (User user : users) {
if (user.getId().equals(id)) {
return user;
}
}
return null;
}
}

三、CacheResolver

其名字已經暗示了其是Cache解析器，用於根據實際狀況來動態解析使用哪一個Cache，如：

Java代碼

public class MyCacheResolver implements CacheResolver {
@Autowired
private CacheManager cacheManager;
@Override
public Collection<? extends Cache> resolveCaches(CacheOperationInvocationContext<?> context) {
List<Cache> caches = new ArrayList<Cache>();
for(String cacheName : context.getOperation().getCacheNames()) {
caches.add(cacheManager.getCache(cacheName));
}
if(context.getTarget() instanceof UserService2) {
caches.add(cacheManager.getCache("user2"));
caches.add(cacheManager.getCache("user3"));
}
return caches;
}
}

context中存放了當前cache的操做類型、目標對象、目標方法、參數信息，這樣咱們能夠根據這些信息來決定使用那些cache； context.getOperation().getCacheNames()獲得當前目標對象/目標方法上配置的cache Name；而後咱們能夠在此基礎上添加額外的cache。

此處須要注意的是即便配置了CacheResolver，也必須在@CacheConfig或方法上的如@CachePut上指定至少一個Cache Name。

四、CacheErrorHandler

用於捕獲從Cache中進行CRUD時的異常的回調處理器。

相關資料

Spring Cache抽象詳解

Spring4新特性

Spring4新特性——泛型限定式依賴注入

Spring4新特性——核心容器的其餘改進

Spring4新特性——Web開發的加強

Spring4新特性——集成Bean Validation 1.1(JSR-349)到SpringMVC

Spring4新特性——Groovy Bean定義DSL

Spring4新特性——更好的Java泛型操做API