SpringBoot之整合JPA

1.添加依赖

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

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

2.在application.yml文件中配置数据源（ddl-auto:建表时使用create , 其他时候用update ）

spring:
  profiles:
    active: dev
  datasource:
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.0.1:3306/dbstudent
    username: root
    password: root
  jpa:
    hibernate:
      ddl-auto: update
    show-sql: true

3.创建Student实体类，id自动增长

package com.zhizhuoedu.student.entity;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

/**
 * @Author: zhao.jw
 * @Description:
 * @Date: Created in 2017-10-10 15:08
 * @Modified By:
 */
@Entity
public class Student {

    @Id
    @GeneratedValue
    private Integer id;

    private String name;

    private Integer age;

    public Student() {
    }

    public Student(String name, Integer age) {
        this.name = name;
        this.age = age;
    }

    public Student(Integer id,String name, Integer age) {
        this.id=id;
        this.name = name;
        this.age = age;
    }

    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 Integer getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

4.IStudentDao ，可自己增加根据某个属性查询的抽象方法，格式为findByXXX

package com.zhizhuoedu.student.dao;

import com.zhizhuoedu.student.entity.Student;
import org.springframework.data.jpa.repository.JpaRepository;

import java.util.List;

/**
 * @Author: zhao.jw
 * @Description:
 * @Date: Created in 2017-10-10 15:55
 * @Modified By:
 */
public interface IStudentDao  extends JpaRepository<Student,Integer>{

    //通过年龄来查询
    public List<Student> findByAge(Integer age);

}

5.StudentController

package com.zhizhuoedu.student.controller;

import com.zhizhuoedu.student.dao.IStudentDao;
import com.zhizhuoedu.student.entity.Student;
import com.zhizhuoedu.student.service.StudentService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;
import java.util.Queue;

/**
 * @Author: zhao.jw
 * @Description:RESTFUL规范对学生信息进行增删改查
 * @Date: Created in 2017-10-10 15:07
 * @Modified By:
 */
@RestController
public class StudentController {

    @Autowired
    private IStudentDao studentDao;
    @Autowired
    private StudentService studentService;

    /**
     * @Author: Zhao.jw
     * @Description:获取学生列表
     */
    @GetMapping("/students")
    public List<Student> getStudents(){
        return studentDao.findAll();
    }

    /**
     * @Author: Zhao.jw
     * @Description:根据学生ID获取学生信息
     */
    @GetMapping("/students/{id}")
    public Student getStudentById(@PathVariable("id") Integer id){
        return studentDao.findOne(id);
    }

    /**
     * @Author: Zhao.jw
     * @Description:根据学生年龄获取学生列表
     */
    @GetMapping("/students/age/{age}")
    public List<Student> getStudentsByAge(@PathVariable("age") Integer age){
        return studentDao.findByAge(age);
    }

    /**
     * @Author: Zhao.jw
     * @Description:添加一个学生
     */
    @PostMapping("/students")
    public String addStudent(String name,Integer age){
        Student entity=new Student(name,age);
        return studentDao.saveAndFlush(entity).toString();
    }

    /**
     * @Author: Zhao.jw
     * @Description:根据学生ID更新学生数据
     */
    @PutMapping("/students/{id}")
    public String updateStudent(@PathVariable("id") Integer id, String name,Integer age){
        Student entity=new Student(id,name,age);
        return studentDao.saveAndFlush(entity).toString();
    }

    /**
     * @Author: Zhao.jw
     * @Description:根据学生ID删除学生数据
     */
    @DeleteMapping("/students/{id}")
    public void delete(@PathVariable("id") Integer id){
        studentDao.delete(id);
    }


    @GetMapping("/students/two")
    public void studentsTwo(){
            studentService.insertTwo();
    }
}

6.StudentService

package com.zhizhuoedu.student.service;

import com.zhizhuoedu.student.dao.IStudentDao;
import com.zhizhuoedu.student.entity.Student;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.naming.Name;

/**
 * @Author: zhao.jw
 * @Description:
 * @Date: Created in 2017-10-10 16:31
 * @Modified By:
 */
@Service
public class StudentService {

    @Autowired
    private IStudentDao studentDao;

    @Transactional
    public void insertTwo(){
        Student entityA=new Student("A",29);
        studentDao.save(entityA);

        Student entityB=new Student("BB",22);
        studentDao.save(entityB);
    }
}