SpringBoot整合SpringData 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>
            <version>8.0.15</version>
        </dependency>

（2）、编写实体类

package cn.coreqi.entities;

import javax.persistence.*;

@Entity
@Table(name = "users")
public class User {
    @Id //标识当前类主键
    @GeneratedValue(strategy = GenerationType.IDENTITY) //自增主键
    private Integer Id;
    @Column(name = "UserName")
    private String UserName;
    @Column(name = "PassWord")
    private String PassWord;
    @Column(name = "Enabled")
    private Integer Enabled;

    public User(String userName, String passWord, Integer enabled) {
        UserName = userName;
        PassWord = passWord;
        Enabled = enabled;
    }

    public Integer getId() {
        return Id;
    }

    public void setId(Integer id) {
        Id = id;
    }

    public String getUserName() {
        return UserName;
    }

    public void setUserName(String userName) {
        UserName = userName;
    }

    public String getPassWord() {
        return PassWord;
    }

    public void setPassWord(String passWord) {
        PassWord = passWord;
    }

    public Integer getEnabled() {
        return Enabled;
    }

    public void setEnabled(Integer enabled) {
        Enabled = enabled;
    }

    public User() {
    }
}

　　

（3）、配置Jpa

spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.url=jdbc:mysql://localhost:3306/JdbcDemo?serverTimezone=UTC
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource

spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=update

（4）、编写一个Dao接口来操作实体类对应的数据表（Repository）

package cn.coreqi.dao;

import cn.coreqi.entities.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;

/**
 * 通过继承JpaRepository来完成对数据库的操作
 * 第一个泛型为实体类名称
 * 第二个泛型为实体类主键类型
 */
@Repository
public interface UserRepository extends JpaRepository<User,Integer> {
　　Page<User> findUsersByUsername(String username, Pageable pageable);
}

    @GetMapping("/findusers")
    public List<User> findUsersByUsername(@RequestParam(required=false) String usernmae, @PageableDefault(page = 0,size = 10,sort = "id,asc") Pageable pageable){
        ...
    }

 使用@PageableDefault注解控制默认的分页参数

相关测试及调用可以借鉴https://www.cnblogs.com/fanqisoft/p/10356698.html