这一篇讲以下三个知识点：
[email protected]——请求映射注解
[email protected]——请求参数
3.ModelAndView——返回模型和视图
示例：（学生信息的查询、添加、修改）——为了方便就不链接数据库直接在类中模拟了一些数据
1.配置springMVC的web.xml
<?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" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>SpringMVC2</display-name>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<!-- 同struts一样，也是需要拦截请求 -->
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring-mvc.xml</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>*.do</url-pattern><!-- 拦截所有以.do结尾的请求 -->
</servlet-mapping>
</web-app>
2.配置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:p="http://www.springframework.org/schema/p"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 使用注解的包，包括子集 -->
<context:component-scan base-package="com.maya"/>
<!-- 视图解析器 -->
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/jsp/" /><!-- 返回视图到这个目录下 -->
<property name="suffix" value=".jsp"></property>
</bean>
</beans>
3.建立model层，实体类student
4.建立controller层，StudentController类
package com.maya.controller;
import java.util.ArrayList;
import java.util.List;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;//是web.servlet.ModelAndView!!!不要选错
import com.maya.model.Student;
@Controller//声明这是控制层
@RequestMapping("/student")//为了区分模块，在请求时通常会在模块前加一个前缀
public class StrudentController {
private static List<Student> studentList=new ArrayList<Student>();
static{//模拟数据
studentList.add(new Student(1, "张三", 11));
studentList.add(new Student(2, "李四", 12));
studentList.add(new Student(3, "王五", 13));
}
@RequestMapping("/list")//定义请求的名字
public ModelAndView list(){//ModelAndView返回模型和视图
ModelAndView mav=new ModelAndView();
mav.addObject("studentList", studentList);
mav.setViewName("student/list");//设置视图的名，student文件名下的list.jsp
return mav;
}
@RequestMapping("/preSave")
public ModelAndView preSave(@RequestParam(value="id",required=false) String id){
//接收前台参数id，因为添加修改都用这一个请求，那么required应设为false，后面定义接收参数的类型
ModelAndView mav=new ModelAndView();
if(id==null){//如果没有接收到参数，说明是添加
mav.setViewName("student/add");//设置视图的名，student文件名下的add.jsp
}else{//否则就是修改了
mav.addObject("student", studentList.get(Integer.parseInt(id)-1));
mav.setViewName("student/update");//设置视图的名，student文件名下的update.jsp
}
return mav;
}
}
5.建立view视图层，因为设定了在jsp文件夹下的student文件下！所以要相应的建立正确的路径
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!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>
<a href="${pageContext.request.contextPath }/student/preSave.do">添加</a>
<table>
<tr>
<th>编号</th>
<th>姓名</th>
<th>年龄</th>
<th>操作</th>
</tr>
<c:forEach var="list" items="${studentList }">
<tr>
<td>${list.id }</td>
<td>${list.name }</td>
<td>${list.age }</td>
<td><a href="${pageContext.request.contextPath }/student/preSave.do?id=${list.id }">修改</a></td>
<td><a href="delete.do?id=${list.id }">删除</a></td>
</tr>
</c:forEach>
</table>
</body>
</html>
时间： 2024-10-07 15:21:00