【SpringBoot】SpringBoot Web开发（八）

　　本周介绍SpringBoot项目Web开发的项目内容，及常用的CRUD操作，阅读本章前请阅读【SpringBoot】SpringBoot与Thymeleaf模版（六）的相关内容

Web开发

　　项目搭建

　　1、新建一个SpringBoot的web项目。pom.xml文件如下：

 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>

     <groupId>com.test</groupId>
     <artifactId>test-springboot-web2</artifactId>
     <version>1.0-SNAPSHOT</version>

     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
         <version>2.1.8.RELEASE</version>
     </parent>

     <properties>

         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>
     </properties>

     <dependencies>

         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>

         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-thymeleaf</artifactId>
         </dependency>

         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
             <scope>test</scope>
         </dependency>

     </dependencies>

     <!-- SpringBoot打包插件，可以将代码打包成一个可执行的jar包 -->
     <build>
         <plugins>
             <plugin>
                 <groupId>org.springframework.boot</groupId>
                 <artifactId>spring-boot-maven-plugin</artifactId>
             </plugin>
         </plugins>
     </build>

 </project>

　　2、配置文件application.properties如下：

 # 项目端口
 server.port=8081
 # 项目访问路径
 server.servlet.context-path=/test

 # 禁用thymeleaf缓存
 spring.thymeleaf.cache=false

 # mvc参数日期格式
 spring.mvc.date-format=yyyy-MM-dd

　　3、在浏览器中使用地址http://localhost:8081/test/即可访问项目

　　4、项目目录结构

　　　　

　　登录功能

　　1、编写登录LoginController.java；逻辑验证用户名和密码，登录成功后在session中存入熟悉loginUser

 package com.test.springboot.controller;

 import org.springframework.stereotype.Controller;
 import org.springframework.util.StringUtils;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestParam;

 import javax.servlet.http.HttpServletRequest;
 import java.util.Map;

 @Controller
 public class LoginController {

     @PostMapping(value = "/user/login")
     public String login(@RequestParam("username") String username,
                         @RequestParam("password") String password,
                         Map<String, Object> map, HttpServletRequest request){
         System.out.println("======");
         if(!StringUtils.isEmpty(username) && "123456".equals(password)) {
             // 登陆成功
             // 防止表单重复提交，可以重定向到主页
             request.getSession().setAttribute("loginUser", username);
             return "redirect:/main.html";
         }else {
             // 登陆失败
             map.put("msg", "用户名或密码错误");
             return "login";
         }

     }

 }

　　2、新建拦截器LoginHandlerInterceptor.java；逻辑：在session中判断是否存在属性loginUser，存在即已登录，不存在未登录

 package com.test.springboot.component;

 import org.springframework.web.servlet.HandlerInterceptor;

 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import java.io.IOException;

 public class LoginHandlerInterceptor implements HandlerInterceptor {

     @Override
     public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws ServletException, IOException {
         Object user = request.getSession().getAttribute("loginUser");
         if(user == null) {
             // 未登录
             request.setAttribute("msg", "没有权限请先登录");
             request.getRequestDispatcher("/index.html").forward(request, response);
         }else{
             // 已登录
             return true;
         }
         return false;
     }
 }

　　3、在SpringMvc中添加拦截器

 package com.test.springboot.config;

 import com.test.springboot.component.LoginHandlerInterceptor;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
 import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

 // @EnableWebMvc // 全面接管SpringMVC，所有的WebMvc自动配置都失效，如静态资源的访问都失效
 @Configuration
 public class MyMvcConfig implements WebMvcConfigurer {

     // 添加视图映射
     @Override
     public void addViewControllers(ViewControllerRegistry registry) {
 //        // 浏览器访问 "/success2" 重定向到 "/success"
 //        registry.addRedirectViewController("/success2", "/success");
 //        // 浏览器访问 "/success2" 转发 "/success"
 //        registry.addViewController("/success3").setViewName("/success");

         // 首页
         registry.addViewController("/").setViewName("login");
         registry.addViewController("/index.html").setViewName("login");

         registry.addViewController("/main.html").setViewName("main");

     }

     // 添加拦截器
     @Override
     public void addInterceptors(InterceptorRegistry registry) {

         // springboot静态映射已做好，无需在拦截器中处理静态资源
         registry.addInterceptor(new LoginHandlerInterceptor()).addPathPatterns("/**")
                 .excludePathPatterns("/", "/index.html", "/user/login");
     }
 }

　　4、编辑登录界面login.html

 <!DOCTYPE html>
 <html lang="en" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <title>login</title>
 </head>
 <body style="text-align: center;">
 <h3>登录</h3>
 <form th:action="@{/user/login}" method="post">
     <p>用户名：<input type="text" name="username" /></p>
     <p>密  码： <input type="password" name="password" /></p>
     <input type="submit" value="提交" />
 </form>
     提示1：[[${msg}]]
 </body>
 </html>

　　5、编辑主页面main.html

 <!DOCTYPE html>
 <html lang="en" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <title>main</title>
 </head>
 <body style="text-align: center;">
     <h3>主页</h3>
     <br>
     [[${session.loginUser}]]
     <h4><a  th:href="@{/emps}">员工列表</a></h4>
     提示-：[[${msg}]]
 </body>
 </html>

　　6、测试，在浏览器中打开地址：http://localhost:8081/test

　　　　

　　CURD功能

　　1、新建员工Controller，内容如下：

package com.test.springboot.controller;

import com.test.springboot.dao.DepartmentDao;
import com.test.springboot.dao.EmployeeDao;
import com.test.springboot.entities.Department;
import com.test.springboot.entities.Employee;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.*;

import java.util.Collection;

@Controller
public class EmployeeController {

    @Autowired
    private EmployeeDao employeeDao;

    @Autowired
    private DepartmentDao departmentDao;

    // 查询所有员工列表
    @GetMapping("/emps")
    public String list(Model model){
        Collection<Employee> employees = employeeDao.getAll();

        // 放在请求域中
        model.addAttribute("emps", employees);

        return "emp/list";
    }

    // 添加员工页面
    @GetMapping("/emp")
    public String toAddPage(Model model){
        // 查询所有部门
        Collection<Department> departments = departmentDao.getDepartments();
        model.addAttribute("depts", departments);
        return "emp/add";
    }

    @GetMapping("/emp/{id}")
    public String toEditPage(@PathVariable("id") Integer id , Model model){

        Employee employee = employeeDao.get(id);
        model.addAttribute("emp", employee);

        Collection<Department> departments = departmentDao.getDepartments();
        model.addAttribute("depts", departments);
        return "emp/add";
    }

    // 员工添加
    @PostMapping("/emp")
    public String addEmp(Employee employee){
        System.out.println("员工信息：" + employee);
        // 返回员工列表界面
        // redirect：表示重定向到某个界面
        // forward：表示转发到某个界面
        employeeDao.save(employee);
        return "redirect:/emps";
    }

    //员工修改；需要提交员工id；
    @PutMapping("/emp")
    public String updateEmployee(Employee employee){
        System.out.println("修改的员工数据："+employee);
        employeeDao.save(employee);
        return "redirect:/emps";
    }

    //员工删除
    @DeleteMapping("/emp/{id}")
    public String deleteEmployee(@PathVariable("id") Integer id){
        employeeDao.delete(id);
        return "redirect:/emps";
    }

}

　　2、员工DAO

 package com.test.springboot.dao;

 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;

 import com.test.springboot.entities.Department;
 import com.test.springboot.entities.Employee;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Repository;

 @Repository
 public class EmployeeDao {

     private static Map<Integer, Employee> employees = null;

     @Autowired
     private DepartmentDao departmentDao;

     static{
         employees = new HashMap<Integer, Employee>();

         employees.put(1001, new Employee(1001, "E-AA", "aa@163.com", 1, new Department(101, "D-AA")));
         employees.put(1002, new Employee(1002, "E-BB", "bb@163.com", 1, new Department(102, "D-BB")));
         employees.put(1003, new Employee(1003, "E-CC", "cc@163.com", 0, new Department(103, "D-CC")));
         employees.put(1004, new Employee(1004, "E-DD", "dd@163.com", 0, new Department(104, "D-DD")));
         employees.put(1005, new Employee(1005, "E-EE", "ee@163.com", 1, new Department(105, "D-EE")));
     }

     private static Integer initId = 1006;

     public void save(Employee employee){
         if(employee.getId() == null){
             employee.setId(initId++);
         }

         employee.setDepartment(departmentDao.getDepartment(employee.getDepartment().getId()));
         employees.put(employee.getId(), employee);
     }

     //查询所有员工
     public Collection<Employee> getAll(){
         return employees.values();
     }

     public Employee get(Integer id){
         return employees.get(id);
     }

     public void delete(Integer id){
         employees.remove(id);
     }
 }

　　3、部门DAO

 package com.test.springboot.dao;

 import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;

 import com.test.springboot.entities.Department;
 import org.springframework.stereotype.Repository;

 @Repository
 public class DepartmentDao {

     private static Map<Integer, Department> departments = null;

     static{
         departments = new HashMap<Integer, Department>();

         departments.put(101, new Department(101, "D-AA"));
         departments.put(102, new Department(102, "D-BB"));
         departments.put(103, new Department(103, "D-CC"));
         departments.put(104, new Department(104, "D-DD"));
         departments.put(105, new Department(105, "D-EE"));
     }

     public Collection<Department> getDepartments(){
         return departments.values();
     }

     public Department getDepartment(Integer id){
         return departments.get(id);
     }

 }

　　4、员工对象

 package com.test.springboot.entities;

 import java.util.Date;

 public class Employee {

     private Integer id;
     private String lastName;

     private String email;
     //1 male, 0 female
     private Integer gender;
     private Department department;
     private Date birth;

     public Integer getId() {
         return id;
     }

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

     public String getLastName() {
         return lastName;
     }

     public void setLastName(String lastName) {
         this.lastName = lastName;
     }

     public String getEmail() {
         return email;
     }

     public void setEmail(String email) {
         this.email = email;
     }

     public Integer getGender() {
         return gender;
     }

     public void setGender(Integer gender) {
         this.gender = gender;
     }

     public Department getDepartment() {
         return department;
     }

     public void setDepartment(Department department) {
         this.department = department;
     }

     public Date getBirth() {
         return birth;
     }

     public void setBirth(Date birth) {
         this.birth = birth;
     }
     public Employee(Integer id, String lastName, String email, Integer gender,
                     Department department) {
         super();
         this.id = id;
         this.lastName = lastName;
         this.email = email;
         this.gender = gender;
         this.department = department;
         this.birth = new Date();
     }

     public Employee() {
     }

     @Override
     public String toString() {
         return "Employee{" +
                 "id=" + id +
                 ", lastName='" + lastName + '\'' +
                 ", email='" + email + '\'' +
                 ", gender=" + gender +
                 ", department=" + department +
                 ", birth=" + birth +
                 '}';
     }

 }

　　5、部门对象

 package com.test.springboot.entities;

 public class Department {

     private Integer id;
     private String departmentName;

     public Department() {
     }

     public Department(int i, String string) {
         this.id = i;
         this.departmentName = string;
     }

     public Integer getId() {
         return id;
     }

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

     public String getDepartmentName() {
         return departmentName;
     }

     public void setDepartmentName(String departmentName) {
         this.departmentName = departmentName;
     }

     @Override
     public String toString() {
         return "Department [id=" + id + ", departmentName=" + departmentName + "]";
     }

 }

　　6、员工列表界面 list.html

 <!DOCTYPE html>
 <html lang="en" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <title>add</title>
 </head>
 <body style="text-align: center;">
     <h3>员工列表</h3>
     <a th:href="@{/emp}">添加员工</a>
     <table>
         <thead>
             <tr>
             <tr>
                 <th>#</th>
                 <th>lastName</th>
                 <th>email</th>
                 <th>gender</th>
                 <th>department</th>
                 <th>birth</th>
                 <th>操作</th>
             </tr>
             </tr>
         </thead>
         <tbody>
             <tr th:each="emp:${emps}">
                 <td th:text="${emp.id}"></td>
                 <td>[[${emp.lastName}]]</td>
                 <td th:text="${emp.email}"></td>
                 <td th:text="${emp.gender} == 0 ? '女' : '男'"></td>
                 <td th:text="${emp.department.departmentName}"></td>
                 <td th:text="${#dates.format(emp.birth, 'yyyy-MM-dd HH:mm')}"></td>
                 <td>
                     <a th:href="@{/emp/} + ${emp.id}">编辑</a>

                     <form id="deleteEmpForm"  method="post" th:action="@{/emp/}+${emp.id}">
                         <input type="hidden" name="_method" value="delete"/>
                         <button th:attr="del_uri=@{/emp/}+${emp.id}" type="submit">删除</button>
                     </form>
                 </td>
             </tr>
         </tbody>
     </table>
 </body>
 </html>

　　7、员工新增界面 add.html

 <!DOCTYPE html>
 <html lang="en" xmlns:th="http://www.thymeleaf.org">
 <head>
     <meta charset="UTF-8">
     <title>list</title>
 </head>
 <body style="text-align: center;">
     <h3>添加员工</h3>

     <!-- 发送put请求修改员工数据 -->
     <!--
         1、SpringMVC中配置HiddenHttpMethodFilter（SpringBoot自动配置）
         2、页面创建一个post表单
         3、创建一个input项，name="_method"; 值就是我们指定的请求方式
     -->
     <form th:action="@{/emp}" method="post">
         <input type="hidden" name="_method" value="put" th:if="${emp!=null}"/>
         <input type="hidden" name="id" th:value="${emp.id}" th:if="${emp!=null}" />
         <p>lastName：<input type="text" name="lastName" th:value="${emp != null}?${emp.lastName}"/></p>
         <p>email： <input type="text" name="email" th:value="${emp != null}?${emp.email}" /></p>
         <p>gender：
             <input type="radio" name="gender" value="1" th:checked="${emp != null}?${emp.gender==1}">男
             <input type="radio" name="gender" value="0" th:checked="${emp != null}?${emp.gender==0 }">女
         </p>
         <p>department：
             <select name="department.id" >
                 <option th:each="dept:${depts}" th:value="${dept.id}" th:selected="${emp != null}?${dept.id == emp.department.id}" th:text="${dept.departmentName}"></option>
             </select>
         <p>birth： <input type="text" name="birth" th:value="${emp != null}?${#dates.format(emp.birth, 'yyyy-MM-dd')}"/></p>
         <input type="submit" th:value="${emp != null? '修改' : '添加'}" />
     </form>
 </body>
 </html>

　　6、测试如下：