Spring学习总结六——SpringMVC一

一：什么是springMVC

MVC,顾名思义，m就是model模型，包括处理业务、访问数据库以及封装数据实体类等，view视图层

负责和用户进行交互，就是展示给用户的部分，包括jsp页面，html等，c就是控制器，是controller层。

大致的访问流程是：

1：浏览器发送请求到服务器，然后服务器将请求分配给dispatcher分发器(在web.xml中配置)

2：然后dispatcher分发器调用handlerMapping将前台请求地址与controller控制器进行匹配，这里就要

用到handlerMapping组件

3：controller控制层调用handlerRequest方法处理请求，当然包括业务以及与数据库交互的部分，然后将

处理结果以及页面封装到ModelAndView对象中返回给核心分发器

4：然后分发器调用viewResolver组件将modelandview中返回的视图名称按照viewResolver进行拼接，得到

访问的视图，然后将数据填充到视图中

5：将jsp处理结果返回到浏览器展示

二：示例演示

下面通过示例来演示：

1：第一步配置环境，在lib中导入如下jar包

2：配置spring容器spring-mvc.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:jdbc="http://www.springframework.org/schema/jdbc" xmlns:jee="http://www.springframework.org/schema/jee"
    xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jpa="http://www.springframework.org/schema/data/jpa"
    xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd
        http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.2.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.2.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
        http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd     
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.2.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd">
    
    <!-- 定义请求处理映射 -->
    <bean id="handlerMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
        <!-- 指定请求与controller对应关系 -->
        <property name="mappings" ref="urlMappings"/>
    </bean>
    
    <!--定义映射关系 -->
    <util:properties id="urlMappings">
        <prop key="/hello.form">helloController</prop>
    </util:properties>
    
    <bean id="helloController" class="com.hlcui.controller.HelloController"></bean>
    
    <!-- 定义viewResolver解析器-->
    <bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
    </beans>
    

3:配置web.xml，dispatcher控制器在这里配置

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
    xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
    http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!-- 指定配置文件的位置 -->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-mvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>*.form</url-pattern>
    </servlet-mapping>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

4：HelloController类

/**
 * 
 */
package com.hlcui.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.Controller;

/**
 * @author Administrator
 *
 */
public class HelloController implements Controller {

    public ModelAndView handleRequest(HttpServletRequest request,
            HttpServletResponse response) throws Exception {
        System.out.println("处理业务逻辑！");
        ModelAndView model = new ModelAndView("hello");
        return model;
    }

}

5：hello.jsp页面

<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
    
    <title>My JSP 'hello.jsp' starting page</title>
    
    <meta http-equiv="pragma" content="no-cache">
    <meta http-equiv="cache-control" content="no-cache">
    <meta http-equiv="expires" content="0">    
    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
    <meta http-equiv="description" content="This is my page">
    <!--
    <link rel="stylesheet" type="text/css" href="styles.css">
    -->

  </head>
  
  <body>
    This is my JSP page. <br>
  </body>
</html>

6：启动服务器，然后通过浏览器访问

访问成功！

三：使用注解的方式对案例进行重构

1:在HelloController类中，可以使用@Controller注解在类上，替代实现Controller接口，需要在

spring容器中配置组件扫描：

<!-- 组件扫描 -->
    <context:component-scan base-package="com.hlcui.controller"/>
    

2:在类上或者方法上使用@RequestMapping注解替换在spring容器中配置urlMapping映射bean

需要在spring容器中配置注解扫描：

<!-- RequestMapping映射配置 -->
    <mvc:annotation-driven/>

3：修改后的类以及配置文件如下

    <!-- 组件扫描 -->
    <context:component-scan base-package="com.hlcui.controller"/>
    
    <!-- RequestMapping映射配置 -->
    <mvc:annotation-driven/>

@Controller
@RequestMapping("/web")
public class HelloController {

    @RequestMapping("/hello.form")
    public String execute(HttpServletRequest request,
            HttpServletResponse response) throws Exception {
        System.out.println("处理业务逻辑！");
        return "hello";
    }

}

4：启动服务器，使用浏览器进行访问

访问成功！