java - 如何传递 ehcache.xml 中声明的 ehCache 装饰器中的依赖项

Question

我想找到一种在 ehCache 装饰器类中使用 Spring 依赖注入(inject)的好方法。我的 ehcache.xml 具有以下缓存配置:

<cache name="MY_CACHE"
       memoryStoreEvictionPolicy="LRU">
    <cacheDecoratorFactory class="org.company.MyCacheDecoratorFactory"/>
</cache>

我有以下装饰器实现:

public class MyCacheDecoratorFactory extends CacheDecoratorFactory implements ApplicationContextAware {

    private MyDependency myDependency;

    @Override
    public Ehcache createDecoratedEhcache(final Ehcache ehcache, final Properties properties) {
        final UpdatingSelfPopulatingCache selfPopulatingCache = new UpdatingSelfPopulatingCache(ehcache,
                new MyUpdatingCacheEntryFactory());
        selfPopulatingCache.setTimeoutMillis(30000);

        return selfPopulatingCache;
    }

    @Override
    public Ehcache createDefaultDecoratedEhcache(final Ehcache ehcache, final Properties properties) {
        return this.createDecoratedEhcache(ehcache, properties);
    }

    @Override
    public void setApplicationContext(final ApplicationContext applicationContext) throws BeansException {
        myDependency = applicationContext.getBean(MyDependency.class);
    }

    private class MyUpdatingCacheEntryFactory implements UpdatingCacheEntryFactory {
        @Override
        public void updateEntryValue(final Object key, final Object value) throws Exception {
            myDependency.update(key, value);
        }

        @Override
        public Object createEntry(final Object key) throws Exception {
            return myDependency.create(key);
        }
    }
}

所以，我不能使用@Autowire直接注入(inject)MyDependency，因为装饰器是通过<cacheDecoratorFactory/>实例化的我的 ehcache.xml 中的标记。

为了能够使用 spring 上下文，我实现了 ApplicationContextAware界面。问题是setApplicationContext()方法在 createDecoratedEhcache() 之后调用，并且当 MyUpdatingCacheEntryFactory 时无法设置依赖项已实例化。

我应该如何将 spring 依赖项正确传递给装饰器？

Answer 1

好的，我可以通过以下方式通过 Spring 完成此操作:

我已删除 <cacheDecoratorFactory/> ehcache.xml 中的标签并添加了一个缓存配置 bean，它使用缓存管理器在初始化时用装饰器替换缓存:

@Component
public class CacheInitConfigurer implements InitializingBean {
    @Autowired
    private CacheManager cacheManager;
    @Autowired
    private MyCacheDecoratorFactory decoratorFactory;

    @Override
    public void afterPropertiesSet() throws Exception {
        final Ehcache myCache = cacheManager.getEhcache("MY_CACHE");
        cacheManager.replaceCacheWithDecoratedCache(myCache,
            decoratorFactory.createDefaultDecoratedEhcache(myCache, null));
    }
}

我已将 MyCacheDecoratorFactory 更改如下:

@Component
public class MyCacheDecoratorFactory extends CacheDecoratorFactory {
    @Autowired
    private MyUpdatingCacheEntryFactory myUpdatingCacheEntryFactory;

    @Override
    public Ehcache createDecoratedEhcache(final Ehcache ehcache, final Properties properties) {
        final SelfPopulatingCache selfPopulatingCache = new UpdatingSelfPopulatingCache(ehcache,
                myUpdatingCacheEntryFactory);
        selfPopulatingCache.setTimeoutMillis(30 * 1000);

        return selfPopulatingCache;
    }

    @Override
    public Ehcache createDefaultDecoratedEhcache(final Ehcache ehcache, final Properties properties) {
        return this.createDecoratedEhcache(ehcache, properties);
    }
}

这对我有用。如果有人有更好的解决方案请告诉我。