基于spring MVC的用户管理
以实际小项目出发来深入理解spring MVC
1.首先是User类
public class User {
private int id;
private String username;
private String password;
private String nickname;
private String email;
省略构造函数和get、set方法
}
2.接着UserController的编写
几点注意：
(1).两种跳转方式，服务器端跳转(带参数) return "redirect:/user/users"; 并返回相关错误信息 和客户端跳转(理解为重定向) return "user/add";
(2).通过model对象将信息返回给视图层；
(3).get和post请求分开处理；
(4).相关的validate验证，需要导入bean-validate.jar包，下面JavaBean中细说。
package com.qzp.web;
import java.util.HashMap;
import java.util.Map;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import com.qzp.model.User;
@Controller
@RequestMapping("/user")
public class UserController {
private Map<String, User> users = new HashMap<String, User>();
public UserController() {
users.put("sdy",new User(1, "sdy","123","宋冬野","[email protected]"));
users.put("ldh",new User(2,"ldh","123","刘德华","[email protected]"));
users.put("gfc",new User(3,"gfc","123","郭富城","[email protected]"));
users.put("lm",new User(4,"lm","123","黎明","[email protected]"));
users.put("zxy",new User(5,"zxy","123","张学友","[email protected]"));
}
//列表页面
@RequestMapping(value="/users",method = RequestMethod.GET)
public String list(Model model){
model.addAttribute("users",users);
return "user/list";
}
//链接到add页面时会使用这段代码
@RequestMapping(value="/add",method = RequestMethod.GET)
public String add(Model model){
//开启ModelDriven
model.addAttribute(new User());
return "user/add";
}
//在具体添加用户时，是post请求，就访问以下的代码
@RequestMapping(value="/add",method = RequestMethod.POST)
//一定要紧跟validate写验证类
public String add(@Validated User user,BindingResult br) {
//如果有错误直接跳转到add视图
if(br.hasErrors()){
return "user/add";
}
users.put(user.getUsername(),user);
return "redirect:/user/users";
}
}
3.考虑到增加信息时，应该有一个服务器端验证，因而此处导入bean-validate.jar包，并修改user文件
package com.qzp.model;
import javax.validation.constraints.Size;
import org.hibernate.validator.constraints.Email;
import org.hibernate.validator.constraints.NotEmpty;
public class User {
private int id;
private String username;
private String password;
private String nickname;
private String email;
public User() {
super();
}
public User(int id, String username, String password, String nickname,
String email) {
super();
this.id = id;
this.username = username;
this.password = password;
this.nickname = nickname;
this.email = email;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@NotEmpty(message="用户名不能为空！")
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
@Size(min=1,max=10,message="密码大于1位小于10位！")
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Email(message="邮箱的格式不正确！")
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
}
4.视图层，首先list页面
jstl标签库要引入，下面是一个迭代标签，spring MVC没有自己的一套标签库，所以这边还是用的strust2的
users是一个map对象，所以要通过他的key来获取值。
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>用户列表</title>
</head>
<body>
<a href="add">用户添加</a><br/>
<c:forEach items="${users}" var="um">
${um.value.id }-
${um.value.username}-
${um.value.password}-
${um.value.nickname}-
${um.value.email}<br/>
</c:forEach>
</body>
</html>
(显示用户名列表页面)执行结果如下：
5.接着是add页面
同样要导入spring的表单标签库，如果验证信息不通过，会提示信息
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib prefix="sf" uri="http://www.springframework.org/tags/form" %>
<html>
<head>
<title>增加页面</title>
</head>
<body>
<!-- 此时没有写action -->
<sf:form method="post" modelAttribute="user">
username：<sf:input path="username"/><sf:errors path="username"/><br/>
password：<sf:password path="password"/><sf:errors path="password"/><br/>
nickname:<sf:input path="nickname"/><br/>
email:<sf:input path="email"/><sf:errors path="email"/><br/>
<input type="submit" value="添加用户"/>
</sf:form>
</body>
</html>
add页面的执行结果，添加成功的话，会跳转到user/list页面之中。
时间： 2024-10-19 10:42:42