springboot写一个简单的增删改后台接口（jpa）
bean实体类：
package com.spring.comtroller.demo.bean;
import javax.persistence.*;
import java.io.Serializable;
@Entity
@Table(name="user", schema = "myapp")
public class Student implements Serializable{
@Id
@GeneratedValue
@Column(name="id")
private long id;
@Column(name = "name")
private String name;
public Student() {
}
public Student(long id, String name) {
this.id = id;
this.name = name;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return "Student{" +
"id=" + id +
", name='" + name + '\'' +
'}';
}
}
controller控制类：
package com.spring.comtroller.demo.controller;
import com.spring.comtroller.demo.bean.Student;
import com.spring.comtroller.demo.result.ResultModel;
import com.spring.comtroller.demo.result.ResultModelTool;
import com.spring.comtroller.demo.service.IStudent;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
@RestController
@RequestMapping(value = "/students")
public class StudentController {
@Autowired
IStudent studentService;
@RequestMapping(value = "/all",method = RequestMethod.GET)
public ResultModel getAllStudent(){
List<Student> studentList = studentService.getAllStudent();
Map<String,List<Student>> studentMap = new HashMap<>();
if (studentList!=null){
studentMap.put("students",studentList);
}
ResultModel resultModel = new ResultModel();
resultModel.setCode(0);
resultModel.setData(studentMap);
return ResultModelTool.handleResultModel(resultModel);
}
@PostMapping(value = "/addStudent")
public ResultModel addStudent(@RequestParam long id,@RequestParam String name){
Student student = new Student(id,name);
int errorCode = studentService.addStudent(student);
ResultModel resultModel = new ResultModel();
resultModel.setCode(errorCode);
resultModel.setData(student);
return ResultModelTool.handleResultModel(resultModel);
}
@PostMapping(value = "/updateStudent")
public ResultModel updateStudent(@RequestParam long id,@RequestParam String name){
Student student = new Student(id,name);
int errorCode = studentService.updateStudent(student);
ResultModel resultModel = new ResultModel();
resultModel.setCode(errorCode);
resultModel.setData(student);
return ResultModelTool.handleResultModel(resultModel);
}
@GetMapping(value = "/deleteStudent/{id}")
public ResultModel deleteStudent(@PathVariable long id){
int errorCode = studentService.deleteStudent(id);
ResultModel resultModel = new ResultModel();
resultModel.setCode(errorCode);
List<Student> studentList = studentService.getAllStudent();
Map<String,List<Student>> studentMap = new HashMap<>();
if (studentList!=null){
studentMap.put("students",studentList);
}
resultModel.setData(studentMap);
return ResultModelTool.handleResultModel(resultModel);
}
}
respository层：
public interface JpaStudentRepository extends JpaRepository<Student,Long>{
}
public interface StudentRepository extends Repository<Student,Long> {
}
service层：
public interface IStudent {
//获取所有的学生
List<Student> getAllStudent();
//增
int addStudent(Student student);
//删
int deleteStudent(long id);
//改
int updateStudent(Student student);
//查
Student queryStudent(long id);
}
service实现类：
package com.spring.comtroller.demo.service;
import com.spring.comtroller.demo.bean.Student;
import com.spring.comtroller.demo.repository.JpaStudentRepository;
import com.spring.comtroller.demo.result.ErrorCode;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;
@Service
public class StudentImpl implements IStudent {
@Autowired
JpaStudentRepository jpaStudentRepository;
@Override
public List<Student> getAllStudent() {
List<Student> students = jpaStudentRepository.findAll();
System.out.println(students.toString());
return students;
}
@Override
public int addStudent(Student student) {
if (jpaStudentRepository.existsById(student.getId())){
System.out.println("user is existed");
return ErrorCode.EXISTUSER;
}
Student saveStudent = jpaStudentRepository.save(student);
if (saveStudent != null && saveStudent.getId() == student.getId()) {
System.out.println("save success");
return ErrorCode.ADDSUCCESS;
} else {
System.out.println("save failure");
return ErrorCode.ADDFAIL;
}
}
@Override
public int deleteStudent(long id) {
if (jpaStudentRepository.existsById(id)) {
jpaStudentRepository.deleteById(id);
System.out.println("删除成功");
return ErrorCode.DELETESUCCESS;
}
System.out.println("删除失败");
return ErrorCode.NOTEXISTUSER;
}
@Override
public int updateStudent(Student student) {
if (jpaStudentRepository.existsById(student.getId())){
jpaStudentRepository.save(student);
System.out.println("更新成功");
return ErrorCode.UPDATESUCCESS;
}
System.out.println("更新失败");
return ErrorCode.UPDATEFAIL;
}
@Override
public Student queryStudent(long id) {
Student student = null;
if (jpaStudentRepository.existsById(id)){
student = jpaStudentRepository.findById(id).get();
System.out.println(student.toString());
}
return student;
}
}
result类：
public interface ErrorCode {
/**
* 10000 网络繁忙
* 10001 无此用户
* 10002 添加成功
* 10003 删除成功
* 10004 更新成功
* 10005 此用户已存在
* 10006 添加失败
* 10007 删除失败
* 10008 更新失败
* -1 请求失败
* 0 请求成功
*/
int NETERROR = 10000;
int NOTEXISTUSER = 10001;
int ADDSUCCESS = 10002;
int DELETESUCCESS = 10003;
int UPDATESUCCESS = 10004;
int EXISTUSER = 10005;
int ADDFAIL = 10006;
int DELETEFAIL = 10007;
int UPDATEFAIL = 10008;
int REQUESTFAIL = -1;
int REQUESTSUCCESS = 0;
}
public class ResultModel implements Serializable{
private int code;
private String msg;
private Object data ;
public ResultModel() {
}
public ResultModel(int errorCode, String msg, Object data) {
this.code = errorCode;
this.msg = msg;
this.data = data;
}
public int getCode() {
return code;
}
public void setCode(int code) {
this.code = code;
}
public String getMsg() {
return msg;
}
public void setMsg(String msg) {
this.msg = msg;
}
public Object getData() {
return data;
}
public void setData(Object data) {
this.data = data;
}
}
package com.spring.comtroller.demo.result;
import java.util.HashMap;
import java.util.Map;
public class ResultModelTool {
public static ResultModel handleResultModel(ResultModel resultModel) {
ResultModel handledModel = new ResultModel();
Map map = new HashMap();
if (resultModel != null) {
int error = resultModel.getCode();
handledModel.setCode(error);
switch (error) {
case 10000:
handledModel.setMsg("网络繁忙,请稍后重试");
handledModel.setData(map);
break;
case 10001:
handledModel.setMsg("无此用户");
handledModel.setData(map);
break;
case 10002:
handledModel.setMsg("添加成功");
handledModel.setData(resultModel.getData());
break;
case 10003:
handledModel.setMsg("删除成功");
handledModel.setData(resultModel.getData());
break;
case 10004:
handledModel.setMsg("更新成功");
handledModel.setData(resultModel.getData());
break;
case -1:
handledModel.setMsg("请求失败");
handledModel.setData(map);
break;
case 10005:
handledModel.setMsg("此用户已存在");
handledModel.setData(map);
break;
case 10006:
handledModel.setMsg("添加失败");
handledModel.setData(map);
break;
case 10007:
handledModel.setMsg("删除失败");
handledModel.setData(map);
break;
case 10008:
handledModel.setMsg("更新失败");
handledModel.setData(map);
break;
default:
handledModel.setMsg("请求成功");
handledModel.setData(resultModel.getData());
break;
}
}
return handledModel;
}
}
