首先创建我们的数据表
如图所示
再进行编写我们的一个前端页面
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>首页</title>
<!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css" integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">
<style>
.info-box{
width: 1000px;
}
</style>
<!-- 调入默认的 js 文件 -->
<script src="https://code.jquery.com/jquery-3.6.0.js"></script>
<!-- 引入 JQ 文件 -->
<!-- <script src="https://code.jquery.com/jquery-3.2.1.min.js"></script>-->
<script src="default.js"></script>
<script>
onload = function () {
// 获取查询所有学员的标签
var btn = document.querySelector(".btn");
// 给标签绑定点击事件
btn.onclick = function () {
// 调用查询所有学员的函数
findAll("tbody");
}
}
</script>
</head>
<body>
<center>
<div class="info-box">
<h1 class="bg-primary">学员信息管理</h1>
<button class="btn btn-info">点击获取所有学员信息</button>
<br>
<br>
<table class="table table-striped table-hover">
<thead>
<tr>
<th>empid</th>
<th>name</th>
<th>deptid</th>
<th>managerid</th>
<th>salary</th>
<th>state</th>
<th>操作</th>
</tr>
</thead>
<!-- 以下内容需要通过 js 添加 -->
<tbody>
</tbody>
</table>
</div>
</center>
</body>
</html>
如图所示
然后来到我们的后端创建项目
项目目录如图所示
然后进行我们的依赖添加
<?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.abc</groupId>
<artifactId>qimozuoye</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>zimozuoye Maven Webapp</name>
<!-- FIXME change it to the project's website -->
<url>http://www.example.com</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>1.8</maven.compiler.source>
<maven.compiler.target>1.8</maven.compiler.target>
</properties>
<dependencies>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.2.9</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<!-- servlet 相关依赖 -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.1</version>
<scope>provided</scope>
</dependency>
<!-- spring 的相关依赖 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.2.21.RELEASE</version>
</dependency>
<!-- spring 的 web 项目依赖 -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>5.2.21.RELEASE</version>
</dependency>
<!-- mysql 的连接依赖 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.48</version>
</dependency>
<!-- json 类型转换依赖 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.80</version>
</dependency>
<!-- lombok 依赖 -->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.google.guava/guava -->
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>25.1-jre</version>
</dependency>
</dependencies>
<build>
<finalName>springWeb</finalName>
<pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
<plugins>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>3.1.0</version>
</plugin>
<!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
<plugin>
<artifactId>maven-resources-plugin</artifactId>
<version>3.0.2</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.1</version>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.2.2</version>
</plugin>
<plugin>
<artifactId>maven-install-plugin</artifactId>
<version>2.5.2</version>
</plugin>
<plugin>
<artifactId>maven-deploy-plugin</artifactId>
<version>2.8.2</version>
</plugin>
</plugins>
</pluginManagement>
</build>
</project>
然后下载我们的lombok插件,不下载的话会导致使用lombok的时候idea会变红
配置TOMCAT
编写jdbc.properties
# 注释说明
# key=value
driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/webdb?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai
user=root
password=123
配置ApplicationContext
<?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:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="com.abcdef"/>
<bean id="employeesService" class="com.abcdef.service.EmployeesService"/>
<bean id="employeesDao" class="com.abcdef.dao.EmployeesDao"/>
<context:property-placeholder location="classpath:jdbc.properties" />
<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
<property name="DriverClassName" value="${driverClassName}"></property>
<property name="Url" value="${url}"></property>
<property name="Username" value="${user}"></property>
<property name="Password" value="${password}"></property>
</bean>
</beans>
然后就可以开始我们的后端编写了
首先编写DButil工具类获取Connection
package com.abcdef.utils;
import com.alibaba.druid.pool.DruidDataSource;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
/**
* @program: qimozuoye
* @description:
* @author:
* @create: 2022-05-27 09:51
* @version:1.0
**/
public class DButil {
public static Connection getConnection() throws SQLException {
ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
DataSource bean = app.getBean(DataSource.class);
Connection connection = bean.getConnection();
return connection;
}
}
pojo类
package com.abcdef.pojo;
import lombok.Data;
import lombok.experimental.Accessors;
import java.math.BigDecimal;
/**
* @program: qimo
* @description:pojo
* @author:
* @create: 2022-05-26 14:44
* @version:1.0
**/
@Accessors(chain = true)
@Data(staticConstructor = "of")
public class Employees {
Integer empid;//id
String name;//名字
Integer deptid;//员工部门1为技术部、2为人事部、3为后勤部
Integer managerid;//工号
BigDecimal salary;//工资
Integer state;//1为在职,2为离职,3为实习
}
BaseController
package com.abcdef.controller;
import com.abcdef.service.EmployeesService;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;
/**
* @program: qimozuoye
* @description: Controller的基类
* @author:
* @create: 2022-05-26 14:49
* @version:1.0
**/
public class BaseController extends HttpServlet {
private EmployeesService employeesService;
public void init(ServletConfig config) throws ServletException {
//通过web程序获取IOC容器
WebApplicationContext wac = WebApplicationContextUtils.getWebApplicationContext(
config.getServletContext()
);
employeesService=wac.getBean(EmployeesService.class);
System.out.println(employeesService);
}
public void defaultSet(HttpServletRequest req, HttpServletResponse resp) {
//同源操作
resp.setHeader("Access-Control-Allow-Origin", "*");
}
//输出操作
public void printHtml(HttpServletResponse resp, String Context) throws IOException {
PrintWriter writer = resp.getWriter();
writer.print(Context);
writer.close();
}
}
先完成我们的findAll.do操作
FindAllController
package com.abcdef.controller;
import com.abcdef.dao.EmployeesDao;
import com.abcdef.pojo.Employees;
import com.abcdef.service.EmployeesService;
import com.alibaba.fastjson.JSONArray;
import lombok.SneakyThrows;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;
/**
* @program: qimozuoye
* @description:接收FindAll.do请求
* @author:
* @create: 2022-05-26 15:16
* @version:1.0
**/
@Controller
@WebServlet("/findAll.do")
public class FindAllController extends BaseController {
@Autowired
EmployeesService employeesService;
@SneakyThrows
@Override
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
System.out.println("接受到了FindAll.do请求");
defaultSet(req,resp);
//设置同源
List<Employees> list= employeesService.findAll();
printHtml(resp, JSONArray.toJSONString(list));
}
@Override
public void init(ServletConfig config) throws ServletException {
WebApplicationContext wac=
WebApplicationContextUtils.getWebApplicationContext(config.getServletContext());
employeesService=wac.getBean(EmployeesService.class);
}
}
EmployeesService
package com.abcdef.service;
import com.abcdef.dao.EmployeesDao;
import com.abcdef.pojo.Employees;
import java.util.List;
/**
* @program: qimozuoye
* @description:业务层
* @author:
* @create: 2022-05-26 15:00
* @version:1.0
**/
public class EmployeesService {
private EmployeesDao employeesDao=new EmployeesDao();//=new EmployeesDao()
public List<Employees> findAll() throws Exception {
return employeesDao.findAll();
}
public int delete(String empid) {
try {
int id=Integer.parseInt(empid);
int result=
employeesDao.delete(id);
return result;
} catch (Exception e) {
e.printStackTrace();
}
return 0;
}
}
dao类
package com.abcdef.dao;
import com.abcdef.pojo.Employees;
import com.abcdef.utils.DButil;
import org.springframework.stereotype.Repository;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
/**
* @program: qimozuoye
* @description: dao类
* @author:
* @create: 2022-05-26 14:51
* @version:1.0
**/
@Repository
public class EmployeesDao {
public List<Employees> findAll() throws SQLException {
Connection con= DButil.getConnection();
List<Employees> list = new ArrayList<>();
try {
// Class.forName("com.mysql.jdbc.Driver");
// Connection con =
// DriverManager.getConnection
// ("jdbc:mysql://localhost:3306/webdb?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai", "root", "123");
PreparedStatement ps = con.prepareStatement("select * from webdb.employees");
ResultSet rs = ps.executeQuery();
while (rs.next()) {
Employees employees = Employees.of()
.setEmpid(rs.getInt("empid"))
.setDeptid(rs.getInt("deptid"))
.setManagerid(rs.getInt("managerid"))
.setName(rs.getString("name"))
.setState(rs.getInt("state"))
.setSalary(rs.getBigDecimal("salary"));
list.add(employees);
System.out.println(list);
}
} catch (Exception e) {
e.printStackTrace();
}
return list;
}
public int delete(Integer empid) throws Exception {
Class.forName("com.mysql.jdbc.Driver");
Connection con =
DriverManager.getConnection
("jdbc:mysql://localhost:3306/webdb?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai", "root", "123");
PreparedStatement ps = con.prepareStatement("delete from webdb.employees where empid = ?");
ps.setInt(1, empid);
int result = ps.executeUpdate();
if(result<=0){
System.out.println("修改失败");
}
return result;
}
}
做到这一步时我们后端就基本上做完了
现在我们返回前端default.js
/**
* @program: qimo
* @description:
* @author:
* @create: 2022-05-26 15:24
* @version:1.0
**/
function findAll(box) {
document.querySelector(box).innerHTML="";
$.ajax({
type: "GET",
// 设置请求地址
url: "http://localhost:8050/findAll.do",
// 设置服务端返回数据类型 URL按照tomcat的端口设置
dataType: "json",
// 传给后端的数据
data:{
},
// 成功回调函数
success:function (data) {
console.log(data);
// 将获取的数据添加至页面
for (let i = 0; i < data.length; i++) {
// 创建节点
var tr = document.createElement('tr');
var empid = document.createElement('td');
var name = document.createElement('td');
var deptid = document.createElement('td');
var managerid = document.createElement('td');
var salary = document.createElement('td');
var state = document.createElement('td');
var ply = document.createElement('td');
// 添加节点中的内容
empid.innerHTML = data[i].empid;
name.innerHTML = data[i].name;
deptid.innerHTML = data[i].deptid;
// 通过初始数据数组获取值
managerid.innerHTML = data[i].managerid;
salary.innerHTML = data[i].salary;
// 通过三元运算进行值的判断
state.innerHTML = data[i].state==1?"在职":
data[i].stustate==2?"离职":"实习";
// 给 ply 添加按钮
ply.innerHTML = '<button class="btn btn-danger"'
+ 'onclick="del('+data[i].empid+')" >删除</button>';
tr.appendChild(empid);
tr.appendChild(name);
tr.appendChild(deptid);
tr.appendChild(managerid);
tr.appendChild(salary);
tr.appendChild(state);
tr.appendChild(ply);
document.querySelector(box).appendChild(tr);
}
},
error:function (jqXHR,textStatus,errorThrown) {
alert(textStatus);
console.log(errorThrown)
}
});
}
function del(id) {
// 查看出入的 id 值
alert(id);
$.ajax({
type: "GET",
url: "http://localhost:8050/del.do",
dataType: "json",
data:{
empid:id
},
success:function (data) {
alert("删除成功");
document.querySelector(".btn").onclick();
},
// 失败回调函数
error:function (jqXHR,textStatus,errorThrown) {
alert("异步请求失败!");
}
});
}
运行结果如下