SpringMVC联手REST实现入门级的CRUD

这是一个WebProject，用到的是spring-framework-3.1.1.RELEASE

首先是web.xml（最终应用访问地址为http://IP:port/contextPath/user/add）

<?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>user</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><load-on-startup>1</load-on-startup></servlet><servlet-mapping><servlet-name>user</servlet-name><url-pattern>/</url-pattern></servlet-mapping><filter><filter-name>SpringCharacterEncodingFilter</filter-name><filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class><init-param><param-name>encoding</param-name><param-value>UTF-8</param-value></init-param></filter><filter-mapping><filter-name>SpringCharacterEncodingFilter</filter-name><url-pattern>/*</url-pattern></filter-mapping></web-app>

然后是SpringMVC的配置文件user-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:mvc="http://www.springframework.org/schema/mvc"xmlns:context="http://www.springframework.org/schema/context"xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsdhttp://www.springframework.org/schema/mvchttp://www.springframework.org/schema/mvc/spring-mvc-3.1.xsdhttp://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"><context:component-scan base-package="com.jadyer"/><mvc:annotation-driven/><bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"><property name="prefix" value="/WEB-INF/jsp/"/><property name="suffix" value=".jsp"/></bean></beans>

用来添加用户信息的//WEB-INF//jsp/user/add.jsp

<%@ page language="java" pageEncoding="UTF-8"%><%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%><%-- 这里并没有指定action=""，说明表单是提交给自己的，说白了就是"哪来的回哪儿去 --%><form:form method="POST" modelAttribute="user">username: <form:input path="username"/><br/>nickname: <form:input path="nickname"/><br/>password: <form:password path="password"/><br/>yourmail: <form:input path="email"/><br/><input type="submit" value="添加新用户"/></form:form>

用来列出所有用户信息的//WEB-INF//jsp/user/list.jsp

<%@ page language="java" pageEncoding="UTF-8"%><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%><c:forEach items="${users}" var="user">${user.value.username}----${user.value.nickname}----${user.value.password}----${user.value.email}    <a href="<%=request.getContextPath()%>/user/${user.value.username}">查看</a>    <a href="<%=request.getContextPath()%>/user/${user.value.username}/update">编辑</a>    <a href="<%=request.getContextPath()%>/user/${user.value.username}/delete">删除</a><br/></c:forEach><br/><a href="<%=request.getContextPath()%>/user/add">继续添加用户</a>

用来显示单个用户信息的//WEB-INF//jsp/user/show.jsp

<%@ page language="java" pageEncoding="UTF-8"%>${user.username}----${user.nickname}----${user.password}----${user.email}<br/><br/><a href="<%=request.getContextPath()%>/user/add">继续添加用户</a>

用来更新单个用户信息的//WEB-INF//jsp/user/update.jsp

<%@ page language="java" pageEncoding="UTF-8"%><%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%><form:form method="POST" modelAttribute="user">username: <form:input path="username"/><br/>nickname: <form:input path="nickname"/><br/>password: <form:password path="password"/><br/>yourmail: <form:input path="email"/><br/><input type="submit" value="更新用户信息"/></form:form>

下面是用户的实体类User.java

package com.jadyer.model;/** * User * @author http://blog.csdn.net/jadyer * @create May 12, 2012 1:24:43 AM */public class User {private String username;private String nickname;private String password;private String email;public User() {}public User(String username, String nickname, String password, String email) {this.username = username;this.nickname = nickname;this.password = password;this.email = email;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getNickname() {return nickname;}public void setNickname(String nickname) {this.nickname = nickname;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}}

最后是核心的UserController.java

package com.jadyer.controller;import java.util.HashMap;import java.util.Map;import org.springframework.stereotype.Controller;import org.springframework.ui.Model;import org.springframework.web.bind.annotation.PathVariable;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestMethod;import com.jadyer.model.User;/** * UserController * @author http://blog.csdn.net/jadyer * @create May 12, 2012 1:26:21 AM */@Controller@RequestMapping("/user")public class UserController {private final static Map<String,User> users = new HashMap<String,User>();//模拟数据源,构造初始数据public UserController(){users.put("张起灵", new User("张起灵", "闷油瓶", "02200059", "[e-mail]"));users.put("李寻欢", new User("李寻欢", "李探花", "08866659", "[e-mail]"));users.put("拓拔野", new User("拓拔野", "搜神记", "05577759", "[e-mail]"));users.put("孙悟空", new User("孙悟空", "美猴王", "03311159", "[e-mail]"));}/** * 添加新用户 * @see 访问/user/add时，GET请求就执行addUser(Model model)方法，POST请求就执行addUser(User user)方法 */@RequestMapping(value="/add", method=RequestMethod.GET)public String addUser(Model model){//这里要传给前台一个空对象，否则会报告java.lang.IllegalStateException异常//异常信息为Neither BindingResult nor plain target object for bean name 'user' available as request attribute//并且传过去的key值要与前台modelAttribute属性值相同，即model.addAttribute("user", new User());//我们也可以写成下面这种方式，此时SpringMVC会自动把对象名转换为小写值作为key，即User-->usermodel.addAttribute(new User());return "user/add";}@RequestMapping(value="/add", method=RequestMethod.POST)public String addUser(User user){ //这里参数中的user就应该与add.jsp中的modelAttribute="user"一致了users.put(user.getUsername(), user);return "redirect:/user/list";}/** * 列出所有用户信息 */@RequestMapping("/list")public String list(Model model){model.addAttribute("users", users);return "user/list";}/** * 查询用户信息 * @see 访问该方法的路径就应该是"/user/具体的用户名" * @see 这里value="/{username}"的写法，需要格外注意一下，它是一个路径变量，此时用来接收前台的一个资源 * @see 这时value="/{username}"就会到方法参数中找@PathVariable String username，并将路径变量值传给username参数 */@RequestMapping(value="/{myname}", method=RequestMethod.GET)public String show(@PathVariable String myname, Model model){model.addAttribute(users.get(myname));return "user/show";}/** * 编辑用户信息 * @see 访问该方法的路径就应该是"/user/具体的用户名/update" */@RequestMapping(value="/{myname}/update", method=RequestMethod.GET)public String update(@PathVariable String myname, Model model){model.addAttribute(users.get(myname));return "user/update";}@RequestMapping(value="/{myname}/update", method=RequestMethod.POST)public String update(User user){users.put(user.getUsername(), user);return "redirect:/user/list"; //也可以retun "forward:/user/list",此时浏览器地址栏会有不同}/** * 删除用户信息 */@RequestMapping(value="/{myname}/delete", method=RequestMethod.GET)public String delete(@PathVariable String myname){users.remove(myname);return "redirect:/user/list"; //删除完成后显示当前存在的所有用户信息}}

转自：http://blog.csdn.net/jadyer/article/details/7574659