spring_MVC_02 CRUD

1.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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <servlet>
    <servlet-name>srpingMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>srpingMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

 2.配置与srpingMVC对应的xml

srpingMVC-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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    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/context
        http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd">
    
    <mvc:annotation-driven/>

    <!-- 配置需要被扫描的包 -->
    <context:component-scan base-package="com.hqh.springmvc"/>

    <!-- 配置对静态资源文件的访问不被过滤 WebContent/resources目录中的文件都能访问 -->
    <mvc:resources location="/resources/" mapping="/resources/**"/>
    
    <!-- 配置返回的数据如何呈现：前缀+逻辑视图+后缀 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    	<property name="prefix" value="/WEB-INF/jsp/"/>
    	<property name="suffix" value=".jsp"/>
    </bean>
</beans>

 

 

控制器

package com.hqh.springmvc.controller;

import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Random;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.SessionAttributes;
import org.springframework.web.servlet.view.InternalResourceViewResolver;

import com.hqh.springmvc.exception.UserException;
import com.hqh.springmvc.model.User;

@Controller
//访问本控制器的方法的路径都需要加/user
@RequestMapping("/user")
//只要往Model中添加loginUser，session中就会存储
@SessionAttributes("loginUser")
public class UserController {
	
	//保证输出的数据与加入Map时的顺序一致，使用LinkedHashMap
	private static Map<String,User> users = new LinkedHashMap<String,User>();
	
	{
		users.put("zs", new User(1,"zs",20,"bj"));
		users.put("ls", new User(2,"ls",20,"sh"));
		users.put("ww", new User(3,"ww",20,"gd"));
		users.put("zl", new User(4,"zl",20,"sz"));
	}
	
	//http://localhost:8080/spring_mvc_user/user/list
	@RequestMapping(value={"/list"})
	public String list(Model model) {
		System.out.println("UserController.list()");
		model.addAttribute("users", users);
		return "user/list";
	}
	
	//查询用GET
	@RequestMapping(value={"/addUser"},method=RequestMethod.GET)
	public String addUser(Model model) {
		//传递页面中需要赋值的对象到request中，这样spring在处理时才能识别到modelAttribute="user"定义的user
		//modelAttribute="user" user(User小写：user)实际代表了User.class
		model.addAttribute(new User());
		return "user/add";
	}
	//注：请求addUser页面与提交表单都是访问的addUser()，通过method来区分
	//1.请求页面使用get方式，故访问method为GET的addUser()
	//2.提交的时候使用post方式，故访问method为POST的addUser()
	//添加用POST
	@RequestMapping(value={"addUser"},method=RequestMethod.POST)
	public String addUser(User user) {
		user.setId(new Random().nextInt(100));
		users.put(user.getName(), user);
		//页面重定向，访问list()
		return InternalResourceViewResolver.REDIRECT_URL_PREFIX+"/user/list";
	}
	
	//REST风格:以资源为导向！
	//通过传入的参数值作为访问方法的后缀名 
	//http://localhost:8080/spring_mvc_user/user/getUser?name=zs --->
	//http://localhost:8080/spring_mvc_user/user/zs
	@RequestMapping(value={"/{name}"},method=RequestMethod.GET)
	public String getUser(@PathVariable String name,Model model) {
		System.out.println("UserController.getUser()");
		model.addAttribute(users.get(name));
		return "user/detail";
	}
	
	@RequestMapping(value="/{name}/update",method=RequestMethod.GET)
	public String updateUser(@PathVariable String name,Model model) {
		model.addAttribute(users.get(name));
		return "user/update";
	}
	@RequestMapping(value="/{name}/update",method=RequestMethod.POST)
	public String updateUser(@PathVariable String name, User user) {
		users.put(name, user);
		return "redirect:/user/list";
	}
	
	
	@RequestMapping(value="/{name}/delete",method=RequestMethod.GET)
	public String deleteUser(@PathVariable String name) {
		users.remove(name);
		return "redirect:/user/list";
	}
	
	@RequestMapping(value="/login",method=RequestMethod.GET)
	public String login() {
		return "user/login";
	}
	
	@RequestMapping(value="/login",method=RequestMethod.POST)
	public String login(String name, Model model) {
		if(!users.containsKey(name)) {
			throw new UserException("用户不存在");
		}
		//将"loginUser"放入session中
		model.addAttribute("loginUser",users.get(name));
		return "redirect:/user/list";
	}
	
	/**
	 * 异常处理
	 * @param ex
	 * @param req
	 * @return
	 */
	@ExceptionHandler(value={UserException.class})
	public String handlerException(Exception ex, HttpServletRequest req) {
		req.setAttribute("ex", ex);
		return "error";
	}
}

 

模型

package com.hqh.springmvc.model;

public class User {
	private int id;
	private String name;
	private int age;
	private String addr;
	
	public User() {
		super();
	}

	public User(int id, String name, int age, String addr) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
		this.addr = addr;
	}

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

	public String getAddr() {
		return addr;
	}

	public void setAddr(String addr) {
		this.addr = addr;
	}
	
	
	
}

 

异常类

package com.hqh.springmvc.exception;

public class UserException extends RuntimeException {

	public UserException() {
		super();
	}

	public UserException(String message, Throwable cause) {
		super(message, cause);
	}

	public UserException(String message) {
		super(message);
	}

	public UserException(Throwable cause) {
		super(cause);
	}

}

 

list.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%
	request.setAttribute("context", this.getServletContext().getContextPath());
%>
<!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="${context}/resource/css/main.css">
</head>
<body>
	<h1>users</h1>
	当前登陆用户：${loginUser.name}<br/>
	<a href="addUser">add user</a><br/>
	<c:forEach items="${users}" var="user">
		<a href="${user.value.name}">${user.value.name}</a>
		<a href="${user.value.name}/update">更新</a>
		<a href="${user.value.name}/delete">删除</a>
		<br/>
	</c:forEach>
</body>
</html>