Java的WEB框架中,Struts2应该是最著名的,不过最近试了试Spring3 MVC,感觉好爽啊,几乎像ASP.Net MVC3一样舒服,以后就用它了。简单记录一下过程,没有技术含量。
1、准备包
下载的是spring framework 3.2.0,从中抽取以下jar到工程的WEB-INF/lib下:
- spring-beans-3.2.0.RELEASE.jar
- spring-context-3.2.0.RELEASE.jar
- spring-core-3.2.0.RELEASE.jar
- spring-expression-3.2.0.RELEASE.jar
- spring-web-3.2.0.RELEASE.jar
- spring-webmvc-3.2.0.RELEASE.jar
另外还需要几个第三方jar包,记录日志和处理json:
- commons-logging-1.1.1.jar
- jackson-core-als-1.9.11.jar
- jackson-mapper-asl-1.9.11.jar
- <?xml version="1.0" encoding="UTF-8"?>
- <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
- xmlns="http://java.sun.com/xml/ns/javaee"
- xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
- xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
- http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
- id="WebApp_ID" version="2.5">
- <!--站点名-->
- <display-name>mvc</display-name>
- <!--指定spring配置文件-->
- <context-param>
- <param-name>contextConfigLocation</param-name>
- <param-value>/WEB-INF/spring-servlet.xml</param-value>
- </context-param>
- <listener>
- <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
- </listener>
- <servlet>
- <!--servlet名字,随意-->
- <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名字-->
- <servlet-name>spring</servlet-name>
- <!--拦截所有请求,对静态文件会有问题,在spring-servlet.xml中解决-->
- <url-pattern>/</url-pattern>
- </servlet-mapping>
- <welcome-file-list>
- <welcome-file>index.htm</welcome-file>
- <welcome-file>index.jsp</welcome-file>
- </welcome-file-list>
- </web-app>
- <?xml version="1.0" encoding="UTF-8"?>
- <beans xmlns="http://www.springframework.org/schema/beans"
- xmlns:context="http://www.springframework.org/schema/context"
- xmlns:p="http://www.springframework.org/schema/p"
- xmlns:mvc="http://www.springframework.org/schema/mvc"
- xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
- xsi:schemaLocation="http://www.springframework.org/schema/beans
- http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
- http://www.springframework.org/schema/context
- http://www.springframework.org/schema/context/spring-context.xsd
- http://www.springframework.org/schema/mvc
- http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
- <!-- 启动注解驱动的Spring MVC功能,注册请求url和注解POJO类方法的映射-->
- <mvc:annotation-driven />
- <!-- 启动包扫描功能,以便注册带有@Controller、@Service、@repository、@Component等注解的类成为spring的bean -->
- <context:component-scan base-package="com.test.mvc.web" />
- <!-- 对模型视图名称的解析,在WEB-INF/jsp目录下找对应的jsp文件 -->
- <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" />
- <!--放过/scripts下的静态文件-->
- <mvc:resources mapping="/scripts/**" location="/scripts/" />
- </beans>
4、WEB-INF/applicationContext.xml
spring的配置文件,由于我们不使用它的其它功能,暂时放个空的就好了。
- <?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:util="http://www.springframework.org/schema/util"
- xsi:schemaLocation="http://www.springframework.org/schema/beans
- http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
- http://www.springframework.org/schema/util
- http://www.springframework.org/schema/util/spring-util-3.0.xsd">
- </beans>
5、写Controller
- package com.test.mvc.web;
- import org.springframework.stereotype.*;
- import org.springframework.web.bind.annotation.*;
- import org.springframework.web.servlet.*;
- /**
- * 控制器,用Controller注解
- */
- @Controller
- public class HomeController {
- /**
- * 映射到/welcome
- */
- @RequestMapping(value = "/welcome")
- public ModelAndView welcome(){
- ModelAndView mv = new ModelAndView("welcome"); //使用welcome.jsp,如果不写,根据url默认也是welcome.jsp
- mv.addObject("hello", "Hello"); //model中增加一个名为hello的字符串
- Client client = new Client();
- client.setName("User");
- mv.addObject("client", client); //再增加一个名为client的自定义对象
- return mv;
- }
- /**
- * 如果不需要Model,直接返String更简单,对应的view为login_page.jsp
- */
- @RequestMapping(value = "/login")
- public String login(){
- return "login_page";
- }
- /**
- * 一个返回json的方法,用ResponseBody标识
- * 可以在url中定义参数中,实现RESTful真是太简单了
- * 传参很灵活,可以从url中取,也可以定义普通的
- */
- @RequestMapping(value="/client/{name}", method = RequestMethod.GET)
- @ResponseBody
- public Client getClient(@PathVariable String name, String title){
- Client client = new Client();
- client.setName(title+ " " + name);
- return client;
- }
- }
里面用到了Client,很简单的POJO:
- package com.test.mvc.web;
- /**
- * 自定义一个POJO
- */
- public class Client {
- private String name;
- public String getName() {
- return name;
- }
- public void setName(String name) {
- this.name = name;
- }
- }
6、写视图
根据spring-servlet.xml中的配置,视图要放到WEB-INF/jsp下,新建welcome.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>Spring MVC</title>
- <script src="scripts/jquery-1.4.2.js"></script>
- <script>
- $(function(){
- $("#btnGet").click(function(){
- $.ajax({
- type: 'GET',
- url : 'client/Tian', //通过url传递name参数
- dataType : 'json',
- data: {title: "Mr"}, //通过data传递title参数
- success : function(data) {
- alert(data.name);
- },
- error : function(data) {
- alert(data.responseText);
- }
- });
- });
- });
- </script>
- </head>
- <body>
- <!-- 显示model中的hello字符串和client对象的name -->
- ${hello}
- ${client.name}
- <br/>
- <input id="btnGet" type="button" value="get client" />
- </body>
- </html>
一切就绪,把Tomcat跑起来吧,用浏览器访问 localhost:8080/mvc/welcome 就能看到页面了。
Spring MVC的实现原理与Struts2不同,底层基于servlet,在方法上进行拦截,因此理论上性能比Struts2要高,有兴趣的可以阅读这篇文章:http://elf8848.iteye.com/blog/698217