搭建springMVC框架

1、新建Dynamic web project工程，选择2.5版本

2、在src下边分好层，注解层在controllor层

3、配置springMVC.xml文件

<?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:aop="http://www.springframework.org/schema/aop"   
    xmlns:context="http://www.springframework.org/schema/context"  
    xmlns:jee="http://www.springframework.org/schema/jee"  
    xmlns:tx="http://www.springframework.org/schema/tx"  
    xsi:schemaLocation="    
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd  
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd  
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd  
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-4.0.xsd  
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">    


<!-- 使用注解的包，包括子集 -->
<context:component-scan base-package="com.spring.test" />


<!-- 视图解析器 -->
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/" />
<property name="suffix" value=".jsp"></property>
</bean>


</beans>  

4、配置web.xml文件

<?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>test1</display-name>
  <welcome-file-list>
    <welcome-file>login.jsp</welcome-file>
  </welcome-file-list>
  
  <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>
<load-on-startup>1</load-on-startup>
<!-- 设置注解为true -->
<async-supported>true</async-supported>
</servlet>
<servlet-mapping>
<servlet-name>springMVC</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
  
</web-app>

问题，如果<async-supported>处报错，解决办法是文件头换成<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">即可。

5、写action层

package com.spring.test;


import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;


import org.apache.catalina.Session;
import org.apache.catalina.connector.Request;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.support.RequestContext;


@Controller
public class loginAction {
@RequestMapping("/login.do")
    public String login(String username,String password){
HttpSession session = getSession();
    System.out.println("进入login方法");
        if ("zhang".equals(username) && "123".equals(password)) {
            System.out.println(username +" 登录成功");
            session.setAttribute("usename", username);//把值传到页面
            return "myjsp/loginSuccess";//逻辑视图名       跳转页面默认为转发
        }
        return "loginError";
    } 

public static HttpSession getSession() { 
   HttpSession session = null; 
   try { 
       session = getRequest().getSession(); 
   } catch (Exception e) {} 
       return session; 
} 
   
public static HttpServletRequest getRequest() { 
   ServletRequestAttributes attrs =(ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); 
   return attrs.getRequest(); 
} 
}

6、写页面

<%@ 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>
<form action="${pageContext.request.contextPath}/login.do" method="post">
   username:<input type="text" name = "username" ><p> 
   password:<input type="password" name = "password" ><p>
   <input type="submit" value="登陆"> 
</form>
</body>
</html>

总结：1、springMVC.xml文件中使用注解的层一定要配置好，层要分好；

2、web.xml文件中配置servlet

3、导入包

4、页面中form中的action路径一定要配置好，尤其注意路径问题