Spring基于注解的缓存配置--web应用实例

之前为大家介绍了如何使用spring注解来进行缓存配置 （EHCache 和 OSCache）的简单的例子，详见

Spring基于注解的缓存配置--EHCacheAND OSCache

现在介绍一下如何在基于注解springMVC的web应用中使用注解缓存，其实很简单，就是将springMVC配置文件与缓存注解文件一起声明到context中就OK了。

下面我就来构建一个基于spring注解小型的web应用,这里我使用EHCache来作为缓存方案。

首先来看一下目录结构，如下：

jar依赖：

ehcache-core-1.7.2.jar
jakarta-oro-2.0.8.jar
slf4j-api-1.5.8.jar
slf4j-jdk14-1.5.8.jar
cglib-nodep-2.1_3.jar
commons-logging.jar
log4j-1.2.15.jar
spring-modules-cache.jar
spring.jar
jstl.jar

standard.jar

接着我们来编写web.xml

<?xml version="1.0" encoding="UTF-8"?>  
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    id="WebApp_ID" version="2.4"  
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">  
    <display-name>SpringCacheWeb</display-name>  
  
    <!-- 由spring加载log4j -->  
    <context-param>  
        <param-name>log4jConfigLocation</param-name>  
        <param-value>classpath:log4j.properties</param-value>  
    </context-param>  
       
    <!-- 声明spring配置文件 -->  
    <context-param>  
        <param-name>contextConfigLocation</param-name>  
        <param-value>  
            /WEB-INF/spring-servlet.xml   
        </param-value>  
    </context-param>  
       
    <!-- 使用UTF-8编码 -->  
    <filter>  
        <filter-name>Set Character Encoding</filter-name>  
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  
        <init-param>  
            <param-name>encoding</param-name>  
            <param-value>UTF-8</param-value>  
        </init-param>  
    </filter>  
    <filter-mapping>  
        <filter-name>Set Character Encoding</filter-name>  
        <url-pattern>*.do</url-pattern>  
    </filter-mapping>  
  
    <!-- 负责初始化log4j-->  
    <listener>  
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>  
    </listener>  
       
    <!-- 负责初始化spring上下文-->  
    <listener>  
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>  
    </listener>  
  
    <!-- springMVC控制器-->  
    <servlet>  
        <servlet-name>spring</servlet-name>  
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  
        <load-on-startup>1</load-on-startup>  
    </servlet>  
  
    <servlet-mapping>  
        <servlet-name>spring</servlet-name>  
        <url-pattern>*.do</url-pattern>  
    </servlet-mapping>  
  
    <session-config>  
        <session-timeout>10</session-timeout>  
    </session-config>  
  
    <welcome-file-list>  
        <welcome-file>index.jsp</welcome-file>  
        <welcome-file>index.html</welcome-file>  
        <welcome-file>index.htm</welcome-file>  
    </welcome-file-list>  
</web-app>

接着我们来编写spring-servlet.xml

<?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:context="http://www.springframework.org/schema/context"  
    xmlns:ehcache="http://www.springmodules.org/schema/ehcache"  
    xsi:schemaLocation="   
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd   
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd   
            http://www.springmodules.org/schema/ehcache http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd"   
            default-lazy-init="true">  
  
  
    <!--启用注解   定义组件查找规则 -->  
    <context:component-scan base-package="com.netqin">  
        <context:include-filter type="annotation"  
            expression="org.springframework.stereotype.Controller" />  
        <context:include-filter type="annotation"  
            expression="org.springframework.stereotype.Service" />  
        <context:include-filter type="annotation"  
            expression="org.springframework.stereotype.Repository" />  
    </context:component-scan>  
  
    <!-- 视图查找器 -->  
    <bean id="viewResolver"  
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">  
        <property name="viewClass"  
            value="org.springframework.web.servlet.view.JstlView">  
        </property>  
        <property name="prefix" value="/WEB-INF/jsp/"></property>  
        <property name="suffix" value=".jsp"></property>  
    </bean>  
       
    <!-- 加载ehcache缓存配置文件    
  
    说明：在这里我遇到了这样一个问题，当使用@Service等注解的方式将类声明到配置文件中时，   
    就需要将缓存配置import到主配置文件中，否则缓存会不起作用   
    如果是通过<bean>声明到配置文件中时，   
    则只需要在web.xml的contextConfigLocation中加入applicationContext-ehcache.xml即可，   
    不过还是推荐使用如下方式吧，因为这样不会有任何问题   
    -->  
    <import resource="classpath:applicationContext-ehcache.xml"/>  
</beans>

ok，我们接着编写applicationContext-ehcache.xml，还记得之前介绍的基于命名空间的配置吗，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:ehcache="http://www.springmodules.org/schema/ehcache"  
    xsi:schemaLocation="   
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd   
            http://www.springmodules.org/schema/ehcache http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd">  
  
  
    <ehcache:config configLocation="classpath:ehcache.xml"  
        id="cacheProvider" />  
    <ehcache:annotations providerId="cacheProvider">  
        <ehcache:caching cacheName="testCache" id="testCaching" />  
        <ehcache:flushing cacheNames="testCache" id="testFlushing" />  
    </ehcache:annotations>  
       
</beans>

ehcache.xml如下：

<?xml version="1.0" encoding="UTF-8"?>  
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  
    xsi:noNamespaceSchemaLocation="ehcache.xsd" updateCheck="true"  
    monitoring="autodetect">  
    <diskStore path="java.io.tmpdir"/>  
    <defaultCache  
            maxElementsInMemory="10000"  
            eternal="false"  
            timeToIdleSeconds="120"  
            timeToLiveSeconds="120"  
            overflowToDisk="true"  
            maxElementsOnDisk="10000000"  
            diskPersistent="false"  
            diskExpiryThreadIntervalSeconds="120"  
            memoryStoreEvictionPolicy="LRU"  
            />  
     <cache name="testCache"  
           maxElementsInMemory="10000"  
           maxElementsOnDisk="1000"  
           eternal="false"  
           overflowToDisk="true"  
           diskSpoolBufferSizeMB="20"  
           timeToIdleSeconds="300"  
           timeToLiveSeconds="600"  
           memoryStoreEvictionPolicy="LFU"  
            />  
</ehcache>

ok，配置文件都完成了，接着我们来编写controller、service和dao

1.CacheDemoController：

package com.netqin.function.cacheDemo;   
  
import org.springframework.beans.factory.annotation.Autowired;   
import org.springframework.stereotype.Controller;   
import org.springframework.ui.Model;   
import org.springframework.web.bind.annotation.RequestMapping;   
  
@Controller  
public class CacheDemoController {   
    @Autowired  
    private CacheDemoService service;   
  
    @RequestMapping("/demo.do")   
    public String handleIndex(Model model) {   
  
        System.out.println(service.getName(0));   
        model.addAttribute("name", service.getName(0));   
  
        return "cacheDemo";   
    }   
    @RequestMapping("/demoFulsh.do")   
   public String handleFulsh(Model model) {   
          service.flush();   
          return "cacheDemo";   
     }   
}

2.CacheDemoService ：

package com.netqin.function.cacheDemo;   
  
import org.springframework.beans.factory.annotation.Autowired;   
import org.springframework.stereotype.Service;   
import org.springmodules.cache.annotations.CacheFlush;   
import org.springmodules.cache.annotations.Cacheable;   
  
@Service  
public class CacheDemoService {   
    @Autowired  
    private CacheDemoDao dao;   
       
    @Cacheable(modelId = "testCaching")   
    public String getName(int id){   
        System.out.println("Processing testCaching");   
        return dao.getName(id);   
    }   
       
    @CacheFlush(modelId = "testFlushing")   
    public void flush(){   
        System.out.println("Processing testFlushing");   
    }   
  
}

我们只对service层加入了注解缓存配置。

接着我们来写一个简单的页面，cacheDemo.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"  
    pageEncoding="UTF-8"%>  
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">  
<html>  
<head>  
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">  
<title>Insert title here</title>  
</head>  
<body>  
CacheDemo:${name}   
</body>  
</html>

ok，一切就绪，我们启动服务器，并访问http://localhost:8080/cache/demo.do

多请求几次，请求两次的输出结果：

Processing testCaching
NameId:0
NameId:0

说明缓存起作用了，ok！

接着我们刷新该缓存，访问http://localhost:8080/cache/demoFulsh.do

再请求http://localhost:8080/cache/demo.do

输出结果：

Processing testCaching
NameId:0
NameId:0
Processing testFlushing
Processing testCaching
NameId:0

缓存刷新成功。 SpringCacheWeb.rar (4.2 MB)