SpringBoot从入门到精通（二十六）超级简单的数据持久化框架！Spring Data JPA 的使用！

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

#数据库连接
spring.datasource.url=jdbc:mysql://localhost:3306/zwz_test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf-8&useSSL=true
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
#jpa配置
spring.jpa.properties.hibernate.hbm2ddl.auto=create
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5InnoDBDialect
#SQL 输出
spring.jpa.show-sql=true
#format 下 SQL 进输出
spring.jpa.properties.hibernate.format_sql=true

package com.weiz.pojo;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.Table;
/**
 * 用户实体类
 *
 * @author
 * @since
*/
@Entity
@Table(name = "Users")
public class Users {
    @Id
    private Long id;
    @Column(length = 32)
    private String name;
    @Column(length = 32)
    private String account;
    @Column(length = 64)
    private String pwd;
    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;
    }
    public String getAccount() {
        return account;
    }
    public void setAccount(String account) {
        this.account = account;
    }
    public String getPwd() {
        return pwd;
    }
    public void setPwd(String pwd) {
        this.pwd = pwd;
    }
}

package com.weiz.dao;
import com.weiz.pojo.Users;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
@Repository
public interface UserRespository extends JpaRepository<Users, Long> {
}

package com.weiz.controller;
import com.weiz.dao.UserRespository;
import com.weiz.pojo.Users;
import com.weiz.utils.JSONResult;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import java.util.Optional;
@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserRespository userRespository;
    @RequestMapping("/save")
    public JSONResult save(){
        Users user = new Users();
        user.setId((long) 1);
        user.setName("spring boot jpa");
        user.setPwd("123456");
        userRespository.save(user);
        return JSONResult.ok("保存成功");
    }
    @RequestMapping("/update")
    public JSONResult update() {
        Users user = new Users();
        user.setId((long) 1);
        user.setName("spring boot jpa update");
        user.setPwd("123456");
        user.setAccount("sbj");
        userRespository.save(user);
        return JSONResult.ok("修改成功");
    }
    @RequestMapping("/delete")
    public JSONResult delete() {
        Users user = new Users();
        user.setId((long) 1);
        userRespository.delete(user);
        return JSONResult.ok("删除成功");
    }
    @RequestMapping("/select")
    public JSONResult select() {
        Optional<Users> users = userRespository.findById((long) 1);
        return JSONResult.ok(users);
    }
}