ss3ex中使用声明式缓存

spring Modules ehcache 存在缺陷，老是配置不成功，通过@Aspect结合annotation来实现了声明式缓存。
1、在spring的xml配置文件中配置aspectj 如下:

<?xml version="1.0" encoding="UTF-8"?>    
<beans xmlns="http://www.springframework.org/schema/beans"   
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   
     xmlns:aop="http://www.springframework.org/schema/aop"   
     xsi:schemaLocation="    
         http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd    
         http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">    
    <aop:aspectj-autoproxy />
</beans>

2、创建注释的定义如下:

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Retention(RetentionPolicy.RUNTIME)
@Target( { ElementType.METHOD })
@Documented
public @interface Ehcache {
	// 缓存名称,默认为空
	String cacheName() default "";

	// 增加缓存还是删除缓存，默认为增加缓存
	boolean addOrdel() default true;
}

3、添加ehcache的配置文件

<cache name="testCache" maxElementsInMemory="500"
		overflowToDisk="true" eternal="true">
		<cacheEventListenerFactory
			class="net.sf.ehcache.distribution.RMICacheReplicatorFactory"
			properties="replicatePuts=false,replicateUpdatesViaCopy=false" />
	</cache>

4、写切面类

import java.io.Serializable;
import java.lang.reflect.Method;

import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.AfterReturning;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

@Component
@Aspect
public class EhcacheAspect {
	private static Cache cache;
	static {
		if (cache == null) {
			cache = CacheManager.getInstance().getCache("testCache");
		}
	}

	@Pointcut("@annotation(Ehcache)")
	public void simplePointcut() {
	}

	@AfterReturning(pointcut = "simplePointcut()")
	public void simpleAdvice() {
		System.out.println("AOP后处理成功");
	}

	/*
	 * 试图得到标注方法的Ehcache类 根据Ehcache的属性进行逻辑处理
	 */
	@Around("simplePointcut()")
	public Object aroundLogCalls(ProceedingJoinPoint joinPoint)
			throws Throwable {
		// 获取连接点的方法签名对象
		MethodSignature joinPointObject = (MethodSignature) joinPoint
				.getSignature();
		// 连接点对象的方法
		Method method = joinPointObject.getMethod();
		// 连接点方法方法名
		String name = method.getName();
		Class<?>[] parameterTypes = method.getParameterTypes();
		// 获取连接点所在的目标对象
		Object target = joinPoint.getTarget();
		// 获取目标方法
		method = target.getClass().getMethod(name, parameterTypes);
		// 返回@AroundPointCut的注释对象
		Ehcache ehcache = method.getAnnotation(Ehcache.class);
		String targetName = joinPoint.getTarget().getClass().toString();
		String methodName = joinPoint.getSignature().getName();
		Object[] arguments = joinPoint.getArgs();
		Object result;
		if ((arguments != null) && (arguments.length != 0)) {
			result = joinPoint.proceed(arguments);
		} else {
			result = joinPoint.proceed();
		}
		if (ehcache.addOrdel()) {
			// 增加缓存
			String cacheKey = getCacheKey(targetName, methodName, arguments);
			Element element = cache.get(cacheKey);
			if (element == null) {
				element = new Element(cacheKey, (Serializable) result);
				cache.put(element);
			}
			return element.getValue();
		} else {
			// 清空缓存
			cache.removeAll();
			return result;
		}

	}

	/**
	 * 获得cache key的方法，cache key是Cache中一个Element的唯一标识 cache key包括
	 * 包名+类名+方法名，如com.co.cache.service.UserServiceImpl.getAllUser
	 */
	private String getCacheKey(String targetName, String methodName,
			Object[] arguments) {
		StringBuffer sb = new StringBuffer();
		sb.append(targetName).append(".").append(methodName);
		if ((arguments != null) && (arguments.length != 0)) {
			for (int i = 0; i < arguments.length; i++) {
				sb.append(".").append(arguments[i]);
			}
		}
		return sb.toString();
	}
}

5、在所有想要缓存的方法上加注标签就能实现缓存了。

//增加缓存
@Ehcache
//删除缓存
@Ehcache(addOrdel=false)