项目在tomcat部署成功，运行却报404错误，把所有文件复制到一个新的项目却能运行，后来又开始404.。。。

ssm项目在tomcat部署成功，运行却报404错误，把所有文件复制到一个新的项目却能运行，后来又开始404，求解！配置xml如下：

web.xml配置：
<?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/j2ee" xmlns:javaee="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/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version="2.4">
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:applicationContext.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <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*:springmvc-servlet.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>springmvc</servlet-name>
    <url-pattern>*.do</url-pattern>
  </servlet-mapping>
  <welcome-file-list>
    <welcome-file>userlogin.jsp</welcome-file>
  </welcome-file-list>
</web-app>

applicationContext.xml配置：

<?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:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"xsi:schemaLocation="http://www.springframework.org/schema/beans        http://www.springframework.org/schema/beans/spring-beans-4.2.xsd        http://www.springframework.org/schema/context        http://www.springframework.org/schema/context/spring-context.xsd        http://www.springframework.org/schema/aop        http://www.springframework.org/schema/aop/spring-aop-4.2.xsd        http://www.springframework.org/schema/tx        http://www.springframework.org/schema/tx/spring-tx.xsd"><!-- 加载classpath下的db.properties文件 --><!-- <context:property-placeholder location="db.properties" /> --><bean id="propertyConfigurer"class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"><!--<property name="location" value="classpath:jdbc.properties" /> --><property name="locations"><list><!-- 属性文件加载列表 --><value>classpath:db.properties</value></list></property></bean><!--第一步： 配置dataSource --><bean id="dataSource" class="${dataSource}" destroy-method="close"><property name="driverClassName" value="${jdbc.driver}" /><property name="url" value="${jdbc.url}" /><property name="username" value="${jdbc.username}" /><property name="password" value="${jdbc.password}" /><!-- 初始化连接大小 --><property name="initialSize" value="${initialSize}"></property><!-- 连接池最大数量 --><property name="maxActive" value="${maxActive}"></property><!-- 连接池最大空闲 --><property name="maxIdle" value="${maxIdle}"></property><!-- 连接池最小空闲 --><property name="minIdle" value="${minIdle}"></property><!-- 获取连接最大等待时间 --><property name="maxWait" value="${maxWait}"></property></bean><!--第二步：配置sqlSessionFactory，SqlSessionFactoryBean是用来产生sqlSessionFactory的 --><bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"><!-- 加载数据源，使用上面配置好的数据源 --><property name="dataSource" ref="dataSource" /><!-- 自动扫描mapping.xml文件 --><property name="mapperLocations" value="classpath:com/mo/ssm/mapper/*.xml"></property></bean><!--配置mybatis接口代理开发 ： 1、接口类名和映射文件必须同名 2、接口类和映射文件必须在同一个目录下 3、 映射文件namespace名字必须是接口的全类路径名 4、接口的方法名必须和映射Statement的id一致 --><!-- 扫描DAO组件 --><!-- MapperScannerConfigurer可以扫描指定包下的 指定接口，然后自动的实现这些接口。 --><bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"><!-- 指定扫描的包名 --><property name="basePackage" value="com.mo.ssm.mapper" /><!-- 通过注解来指定扫描的接口，即当配置了该 注解以后，MapperScannerConfigurer会扫描 包下带有该注解的接口。 该注解需要自定义，当配置它时会扫描带有 注解的接口，不配置时会扫描所有的接口。 --><property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property></bean><!-- 开启IOC注解扫描 属于spring范围 --><context:component-scan base-package="com.mo.ssm.*" /><!-- 第三步：配置事务管理 --><bean id="transactionManager"class="org.springframework.jdbc.datasource.DataSourceTransactionManager"><property name="dataSource" ref="dataSource" /></bean><!-- 配置通知 --><tx:advice id="txAdvice" transaction-manager="transactionManager"><tx:attributes><tx:method name="add*" propagation="REQUIRED" /><tx:method name="append*" propagation="REQUIRED" /><tx:method name="insert*" propagation="REQUIRED" /><tx:method name="save*" propagation="REQUIRED" /><tx:method name="update*" propagation="REQUIRED" /><tx:method name="modify*" propagation="REQUIRED" /><tx:method name="edit*" propagation="REQUIRED" /><tx:method name="delete*" propagation="REQUIRED" /><tx:method name="remove*" propagation="REQUIRED" /><tx:method name="repair" propagation="REQUIRED" /><tx:method name="delAndRepair" propagation="REQUIRED" /><tx:method name="get*" propagation="SUPPORTS" /><tx:method name="find*" propagation="SUPPORTS" /><tx:method name="load*" propagation="SUPPORTS" /><tx:method name="search*" propagation="SUPPORTS" /><tx:method name="datagrid*" propagation="SUPPORTS" /><tx:method name="*" propagation="SUPPORTS" /></tx:attributes></tx:advice><!-- 配置拦截service --><aop:config><aop:advisor advice-ref="txAdvice"pointcut="execution(* com.mo.ssm.service.*.*(..))" /></aop:config></beans>

springmvc-servlet.xml配置：

<?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:mvc="http://www.springframework.org/schema/mvc"
  xmlns:context="http://www.springframework.org/schema/context"
  xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
  xsi:schemaLocation="http://www.springframework.org/schema/beans 
    http://www.springframework.org/schema/beans/spring-beans-3.2.xsd 
    http://www.springframework.org/schema/mvc 
    http://www.springframework.org/schema/mvc/spring-mvc-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/aop 
    http://www.springframework.org/schema/aop/spring-aop-3.2.xsd 
    http://www.springframework.org/schema/tx 
    http://www.springframework.org/schema/tx/spring-tx-3.2.xsd">

    <!-- 注解方式 -->
    <mvc:annotation-driven />
  <!-- 文件扫描 -->
  <context:component-scan base-package="com.mo.ssm.controller"></context:component-scan>

  <!-- annotation-driven:默认创建了多个对象：RequestMappingHandlerMapping，RequestMappingHandlerAdapter
    也就提供对json格式支持
   -->
  <mvc:annotation-driven/>
  <!-- 视图解析器 -->
  <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/" />
    <property name="suffix" value=".jsp" />
  </bean>
</beans>

jsp登录页面：

  <body>
    登录首页<br>
    <form action="login" method="get">
             用户名<input id="username" type="text"/><br/>
             密码<input id="password" type="password"/><br/>  
    <input id="loginsubmit" type="submit" value="登录"/> 
    <input type="reset" value="重置"><br/>       
    </form>
  </body>

controller页面：
package com.mo.ssm.controller;

import javax.annotation.Resource;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

import com.mo.ssm.entity.Rtuusertab;
import com.mo.ssm.service.RtuusertabService;

@Controller
public class RtuusertabController {

@Resource
private RtuusertabService rService;

@RequestMapping(value="/login.do",method=RequestMethod.GET)
public ModelAndView login(String username,String password) {
Rtuusertab rtuusertab=rService.findNameAndPass(username, password);
if (null!=rtuusertab) {
ModelAndView mView=new ModelAndView("list");
return mView;
}
return new ModelAndView("userlogin");
}
}