springmvc的工作原理是：1、浏览器发送请求给dispatcherservlet；2、根据请求找到对应的controller；3、返回modelandview；4、找到对应的视图对象view并渲染；5、返回到浏览器。
SpringMVC工作原理：
（推荐学习：java入门程序）
1、浏览器发送指定的请求都会交给DispatcherServlet,他会委托其他模块进行真正的业务和数据处理；
2、DispatcherServlet会查找到HandleMapping,根据浏览器的请求找到对应的Controller，并将请求交给目标Controller；
3、目标Controller处理完业务后，返回一个ModelAndView给DispatcherServlet；
4、DispatcherServlet通过ViewResolver视图解析器找到对应的视图对象View；
4、视图对象View负责渲染，并返回到浏览器。
（视频教程推荐：java视频教程）
下面我们来看一下代码实例：
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_2_5.xsd"
version="2.5">
<display-name>springmvc</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<!-- spring入口 -->
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- 项目启动时，就加载并实例化 -->
<load-on-startup>1</load-on-startup>
</servlet>
<!-- 拦截所有不包括jsp的请求 -->
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
</web-app>springmvc-servlet.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:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- springmvc注解驱动 -->
<mvc:annotation-driven></mvc:annotation-driven>
<!-- 开启注解扫描 -->
<context:component-scan base-package="cn.itcast.controller"></context:component-scan>
<!-- 配置试图解析器
prefix:指定试图所在目录
suffix:指定视图的后缀名
例如：prifex="/WEB-INF/jsp/",suffix=".jsp",当viewname="test"时，跳转到/WEB-INF/jsp/test.jsp页面
-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>
</beans>UserControll类
@Controller
@RequestMapping("user")
public class UserController {
@RequestMapping("findAllUsers")
public ModelAndView findAllUsers() {
ModelAndView mv = new ModelAndView();
ArrayList<User> users = new ArrayList<User>();
for (int i = 0; i < 5; i++) {
User user = new User();
user.setUsername("zs" + i);
user.setAge(20 + i);
user.setIncome(16000.0+i*100);
user.setIsMarry(false);
user.setHobby(new String[] { "篮球"+i, "足球"+i });
users.add(user);
}
mv.addObject("users", users);
mv.setViewName("users");
return mv;
}
}实体类
public class User implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
private String username;
private Integer age;
private Boolean isMarry;
private Double income;
private String[] hobby;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Boolean getIsMarry() {
return isMarry;
}
public void setIsMarry(Boolean isMarry) {
this.isMarry = isMarry;
}
public Double getIncome() {
return income;
}
public void setIncome(Double income) {
this.income = income;
}
public String[] getHobby() {
return hobby;
}
public void setHobby(String[] hobby) {
this.hobby = hobby;
}
@Override
public String toString() {
return "User [username=" + username + ", age=" + age + ", isMarry=" + isMarry + ", income=" + income
+ ", hobby=" + Arrays.toString(hobby) + "]";
}
}jsp页面
<%@ 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>
<link rel="stylesheet" type="text/css" href="/css/user.css" />
</head>
<body>
<table id="customers">
<tr>
<th>用户名</th>
<th>年龄</th>
<th>收入</th>
<th>婚姻状态</th>
<th>兴趣爱好</th>
</tr>
<!-- 遍历后台传递的集合数据 -->
<c:forEach items="${users}" var="user">
<tr>
<td>${user.username}</td>
<td>${user.age}</td>
<td>${user.income}</td>
<!-- 判婚姻状态 -->
<td><c:choose>
<c:when test="${user.isMarry}">已婚</c:when>
<c:otherwise>未婚</c:otherwise>
</c:choose>
</td>
<td>
<!-- 再次遍历用户爱好 -->
<c:forEach items="${user.hobby}" var="hobby" varStatus="status">
${hobby}
<!-- 如果不是最后一个爱好，则加上逗号，否则就不加 -->
<c:if test="${!status.last}">,</c:if>
</c:forEach>
</td>
</tr>
</c:forEach>
</table>
</body>
</html> 
