SpringMVC联手REST实现入门级的CRUD

openkk 12年前

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

 

首先是web.xml
    <?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>  
</strong></span>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.xsd                                http://www.springframework.org/schema/mvc                                http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd                                http://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>  
</strong></span>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>  
</strong></span>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>  
</strong></span>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>  
</strong></span>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>  
</strong></span>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;            }        }  
</strong></span>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", "menyouping@yeah.net"));                users.put("李寻欢", new User("李寻欢", "李探花", "08866659", "lixunhuan@gulong.cn"));                users.put("拓拔野", new User("拓拔野", "搜神记", "05577759", "tuobaye@manhuang.cc"));                users.put("孙悟空", new User("孙悟空", "美猴王", "03311159", "sunhouzi@xiyouji.zh"));            }                        /**            * 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-->user                model.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            }        }  
</strong></span>转自:http://blog.csdn.net/jadyer/article/details/7574659