使用SpringBoot+Mysql+JPA實現對數據庫的增刪改查和分頁
JPA是Java Persistence API的簡稱,中文名Java持久層API,是JDK 5.0注解或XML描述對象-關系表的映射關系,並將運行期的實體對象持久化到數據庫中。
使用Springboot和jpa對數據庫進行操作時,能夠大大減少我們的工作量,在jpa中,已經在底層封裝好了增刪查的功能和sql語句,可以使我們進行快速開發
項目流程
一、新建一個項目







二、配置文件

#數據源配置 spring.datasource.type=com.alibaba.druid.pool.DruidDataSource spring.datasource.driverClassName=com.mysql.cj.jdbc.Driver spring.datasource.url=jdbc:mysql://localhost:3306/stu?useSSL=false&useUnicode=true&characterEncoding=utf-8&autoReconnect=true&serverTimezone=Asia/Shanghai spring.datasource.username=root spring.datasource.password=root spring.datasource.initialSize=20 spring.datasource.minIdle=50 spring.datasource.maxActive=500 #上下文配置 server.port=8888 server.servlet.context-path=/stu #配置jpa #幫我們自動生成表結構 spring.jpa.properties.hibernate.hbm2ddl.auto=update spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect spring.jpa.show-sql= true spring.jpa.properties.hibernate.enable_lazy_load_no_trans=true

<?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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.kude.stu</groupId>
<artifactId>kudestu</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>kudestu</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- druid數據庫連接池-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.10</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.github.pagehelper/pagehelper-spring-boot-starter -->
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper-spring-boot-starter</artifactId>
<version>1.2.10</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
三、Mysql數據庫
新建一個數據庫stu,創建student表和user表



四、后端實現


student實體類
package com.kude.stu.kudestu.stu.entity;
import javax.persistence.*;
import javax.xml.soap.Name;
@Entity
@Table(name = "student")
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer id;
private String name;
private int age;
private String sex;
@Override
public String toString() {
return "Student{" +
"id=" + id +
", name='" + name + '\'' +
", age=" + age +
", sex='" + sex + '\'' +
'}';
}
public Integer getId() {
return id;
}
public void setId(Integer 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 getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Student() {
}
}
user實體類
package com.kude.stu.kudestu.stu.entity;
import javax.persistence.*;
@Entity
@Table(name="user")
public class User {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
private String username;
private String password;
public User() {
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", password='" + password + '\'' +
'}';
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}

StudentDao接口
package com.kude.stu.kudestu.stu.dao;
import com.kude.stu.kudestu.stu.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
import java.util.List;
public interface StudentDao extends JpaRepository<Student,Integer> {
Student findStuById(Integer id);
@Query(name = "findStuByName",nativeQuery = true,value = "select * from student where name=:name ")
List<Student> findStuByName(@Param("name") String name);
}
UserDao接口
package com.kude.stu.kudestu.stu.dao;
import com.kude.stu.kudestu.stu.entity.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.query.Param;
public interface UserDao extends JpaRepository<User,Integer> {
/**
* 根據id查詢
*/
User findUserById(int id);
@Query(name = "login",nativeQuery = true,value = "select * from user where username=:username and password=:password")
User login(@Param("username") String username,@Param("password") String password);
}

StudentService接口
package com.kude.stu.kudestu.stu.service;
import com.kude.stu.kudestu.stu.entity.Student;
import org.springframework.data.domain.Page;
import java.util.List;
public interface StudentService {
Student save(Student student);
Student update(Student student);
void delete(Integer id);
Student findStuById(Integer id);
List<Student> findStuByName(String name);
/**
* 分頁查詢所有數據
* @param page 當前頁
* @param pageSize 每頁記錄數
* @return
*/
Page<Student> findAll(int page,int pageSize);
}
StudentServiceImpl實現類
package com.kude.stu.kudestu.stu.service;
import com.kude.stu.kudestu.stu.dao.StudentDao;
import com.kude.stu.kudestu.stu.entity.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class StudentServiceImpl implements StudentService {
@Autowired
private StudentDao studentDao;
@Override
public Student save(Student student) {
return studentDao.save(student);
}
@Override
public Student update(Student student) {
return studentDao.save(student);
}
@Override
public void delete(Integer id) {
studentDao.deleteById(id);
}
@Override
public Student findStuById(Integer id) {
return studentDao.findStuById(id);
}
@Override
public List<Student> findStuByName(String name) {
return studentDao.findStuByName(name);
}
@Override
public Page<Student> findAll(int page, int pageSize) {
Pageable pageable = PageRequest.of(page,pageSize);
return studentDao.findAll(pageable);
}
}
UserService接口
package com.kude.stu.kudestu.stu.service;
import com.kude.stu.kudestu.stu.entity.User;
import java.util.List;
public interface UserService {
List<User> findAll();
User findUserById(int id);
User save(User user);
User update(User user);
User login(String username,String password);
}
UserServiceImpl實現類
package com.kude.stu.kudestu.stu.service;
import com.kude.stu.kudestu.stu.dao.UserDao;
import com.kude.stu.kudestu.stu.entity.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserDao userDao;
@Override
public List<User> findAll() {
return userDao.findAll();
}
@Override
public User findUserById(int id) {
return userDao.findUserById(id);
}
@Override
public User save(User user) {
return userDao.save(user);
}
@Override
public User login(String username, String password) {
return userDao.login(username,password);
}
@Override
public User update(User user) {
return null;
}
}

StudentController類
package com.kude.stu.kudestu.stu.controller;
import com.kude.stu.kudestu.stu.entity.Student;
import com.kude.stu.kudestu.stu.service.StudentService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.web.bind.annotation.*;
import javax.servlet.http.HttpServletResponse;
import java.util.List;
@RestController
@RequestMapping("/s")
public class StudentController {
@Autowired
private StudentService studentService;
/**
* 添加學生
* @param student 要添加的學生對象
* @return
*/
@PostMapping("/add")
public Student save(Student student){
return studentService.save(student);
}
/**
* 修改學生
* @param student 要修改的學生對象
* @return
*/
@PostMapping("/update")
public Student update(Student student){
return studentService.save(student);
}
/**
* 刪除學生
* @param id 要刪除學生對象的id
*/
@GetMapping("/del/{id}")
public String del(@PathVariable Integer id){
studentService.delete(id);
return "yes";
}
/**
* 通過姓名查詢學生信息
* @param name 要查詢的學生的姓名
* @return
*/
@GetMapping("/findByName/{name}")
public List<Student> findStuByName(@PathVariable String name){
return studentService.findStuByName(name);
}
/**
* 分頁查詢
* @param page
*
* @return
*/
@GetMapping("/query")
public Page<Student> findByPage(Integer page, HttpServletResponse response){
response.setHeader("Access-Control-Allow-Origin","*");
if(page==null||page<=0){
page=0;
}else {
page -=1;
}
return studentService.findAll(page,5);
}
}
UserController類
package com.kude.stu.kudestu.stu.controller;
import com.kude.stu.kudestu.stu.entity.User;
import com.kude.stu.kudestu.stu.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import java.util.List;
/**
*處理用戶信息的控制層
* @author 張玉賢
* */
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
private UserService userService;
/**
*查詢用戶的方法
*
*/
@RequestMapping(value = "/findAll",method = RequestMethod.POST)
public List<User> findAll(){
return userService.findAll();
}
/**
* 根據id查詢用戶
*/
@RequestMapping(value = "/findById")
public User findUserById(int id){
return userService.findUserById(id);
}
/**
* 注冊用戶
*/
@RequestMapping(value = "/reg",method = RequestMethod.POST)
public User reg(User user){
return userService.save(user);
}
/**
* 用戶登錄
*/
@PostMapping("/login")
public User login(String username,String password){
return userService.login(username,password);
}
}
五、前端分頁實現



新建一個項目

百度搜索菜鳥教程並打開




在js目錄下新建一個jquery.js

將所有內容全選復制粘貼進js目錄下的jquery.js中保存即可

index.html
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<script src="js/jquery.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript">
var page = 1;
var tp = 0;
$(function(){
showData();
});
function upPage(){
if(page>1){
page--;
showData();
}
}
function downPage(){
if(page<tp){
page++;
showData();
}
}
function showData(){
$.ajax({
url:'http://localhost:8888/stu/s/query?page='+page,
success:function(result){
var rel = result.content;
tp = result.totalPages;
var htmlStr = "<table width='80%' algin='center' border='1'>"+
"<tr><th>ID</th><th>姓名</th><th>年齡</th><th>性別</th><th>操作</th></tr>";
for(var i=0;i<rel.length;i++){
var stu = rel[i];
htmlStr += "<tr><td>"+stu.id+"</td><td>"+stu.name+"</td><td>"+stu.age+"</td><td>"+stu.sex+"</td>"+
"<td><a href=''>修改</a> <a href='http://localhost:8888/stu/s/del/"+stu.id+"'>刪除</a></td></tr>";
}
htmlStr += "</table>";
$("#show").html(htmlStr);
}
});
}
</script>
</head>
<body>
<h1 style="text-align: center;">學生管理系統</h1>
<hr>
<a href="add.html">添加學生</a>
<div id="show">
</div>
<a href="javascript:upPage();">上一頁</a> <a href="javascript:downPage();">下一頁</a>
</body>
</html>
add.html
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title></title> </head> <body> <h1>添加學生</h1> <hr> <form action="http://localhost:8888/stu/s/add" method="post"> <p> 姓名:<input type="text" name="name" /> </p> <p> 年齡:<input type="text" name="age" /> </p> <p> 性別: <input type="radio" name="sex" value="男" checked />男 <input type="radio" name="sex" value="女" />女 </p> <p> <input type="submit" value="保存" /> </p> </form> </body> </html>
六、頁面顯示




七、Postman測試

User測試









Student測試

















