之前為大家介紹了如何使用spring注解來進行緩存配置 （EHCache 和 OSCache）的簡單的例子，詳見
Spring基于注解的緩存配置--EHCache?AND OSCache
現在介紹一下如何在基于注解springMVC的web應用中使用注解緩存，其實很簡單，就是將springMVC配置文件與緩存注解文件一起聲明到context中就OK了。
下面我就來構建一個基于spring注解小型的web應用,這里我使用EHCache來作為緩存方案
jar依賴：
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
接著我們來編寫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加載log4j --><context-param><param-name>log4jConfigLocation</param-name><param-value>classpath:log4j.properties</param-value></context-param><!-- 聲明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編碼 --><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><!-- 負責初始化log4j--><listener><listener-class>org.springframework.web.util.Log4jConfigListener</listener-class></listener><!-- 負責初始化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>
?接著我們來編寫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.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsdhttp://www.springmodules.org/schema/ehcache http://www.springmodules.org/schema/cache/springmodules-ehcache.xsd"default-lazy-init="true"><!--啟用注解 定義組件查找規則 --><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><!-- 視圖查找器 --><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><!-- 加載ehcache緩存配置文件 說明：在這里我遇到了這樣一個問題，當使用@Service等注解的方式將類聲明到配置文件中時，就需要將緩存配置import到主配置文件中，否則緩存會不起作用如果是通過<bean>聲明到配置文件中時，則只需要在web.xml的contextConfigLocation中加入applicationContext-ehcache.xml即可，不過還是推薦使用如下方式吧，因為這樣不會有任何問題--><import resource="classpath:applicationContext-ehcache.xml"/>
</beans>
?
ok，我們接著編寫applicationContext-ehcache.xml，還記得之前介紹的基于命名空間的配置嗎，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.xsdhttp://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"/><defaultCachemaxElementsInMemory="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，接著我們來編寫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 {@Autowiredprivate 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 {@Autowiredprivate 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");}}
?
我們只對service層加入了注解緩存配置。
?
接著我們來寫一個簡單的頁面，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，一切就緒，我們啟動服務器，并訪問http://localhost:8080/cache/demo.do
?
多請求幾次，請求兩次的輸出結果：
Processing testCaching
NameId:0
NameId:0
?
說明緩存起作用了，ok！
?
接著我們刷新該緩存，訪問http://localhost:8080/cache/demoFulsh.do
再請求http://localhost:8080/cache/demo.do
輸出結果：
Processing testCaching
NameId:0
NameId:0
Processing testFlushing
Processing testCaching
NameId:0
?
緩存刷新成功。
)
