springboot2.0 集成springDataJpa

1.pom.xml添加 spring-boot-starter-data-jpa 依赖

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
 
        <!-- 数据库连接池采用阿里druid-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.9</version>
        </dependency>
 
        <dependency>
            <groupId>com.googlecode.log4jdbc</groupId>
            <artifactId>log4jdbc</artifactId>
            <version>1.2</version>
        </dependency>
 
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

2.application.yml配置

spring:
  datasource:
    driver-class-name: net.sf.log4jdbc.DriverSpy
    url: jdbc:log4jdbc:mysql://localhost:3306/datebasename?createDatabaseIfNotExist=true&autoReconnect=true&useUnicode=true&characterEncoding=utf-8
    username: root
    password: root
    initialSize: 5
    minIdle: 5
    maxActive: 2000
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 300000
    validationQuery: select 'x'
    testWhileIdle: true
    testOnBorrow: true
    testOnReturn: true
    poolPreparedStatements: true
    maxPoolPreparedStatementPerConnectionSize: 20
    filters: stat,slf4j
    connectionProperties=druid.stat.mergeSql: true;druid.stat.slowSqlMillis=5000
    type: com.alibaba.druid.pool.DruidDataSource
    useGlobalDataSourceStat: true
  jpa:
    database: mysql
    #配置自动建表：updata:没有表新建，有表更新操作,控制台显示建表语句
    hibernate:
      ddl-auto: update
    show-sql: true

3.BaseEntity类和实体类

import lombok.Data;
import javax.persistence.*;
import java.io.Serializable;
import java.util.Date;
 
/**
 * @Description: TODO(base-entity)
 * @Author: 爱飘de小子  15:54
 * @Date: 2018年08月03日 15点54分
 */
@Data
@MappedSuperclass
public abstract class BaseEntity implements Serializable {
 
    private static final long serialVersionUID = -4505117821220216969L;
 
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id", nullable = false, columnDefinition = "BIGINT UNSIGNED")
    private Long id;
 
 
    @Column(name = "create_time", columnDefinition = "datetime  COMMENT '创建时间'")
    private Date createTime;
 
 
    @Column(name = "update_time", columnDefinition = "datetime  COMMENT '修改时间'")
    private Date updateTime;
 
 
    /**
     * 数据插入前的操作
     */
    @PrePersist
    public void setInsertBefore() {
        this.createTime = new Date();
        this.updateTime = new Date();
    }
 
    /**
     * 数据修改前的操作
     */
    @PreUpdate
    public void setUpdateBefore() {
        this.updateTime = new Date();
    }
 
}

import lombok.Data;
 
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Index;
import javax.persistence.Table;
import java.io.Serializable;
 
/**
 * 普通实体类
 * @Author: 爱飘de小子  10:43
 * @Date: 2018年09月10日 10点43分
 */
@Data
@Entity
//列orderNo添加索引
@Table(name="NoticeHisResult",indexes = {@Index(columnList = "orderNo")})
public class Notice extends BaseEntity implements Serializable {
 
    private static final long serialVersionUID = 1620243840780887725L;
 
    @Column(name = "orderNo",nullable = false,columnDefinition = "varchar(50) COMMENT '订单号'")
    private String orderNo;
 
    @Column(name = "notice_status", columnDefinition = "int(10) COMMENT '通知状态： 1-成功 0-失败'")
    private Integer noticeStatus;
 
    @Column(name = "notice_desc", columnDefinition = "varchar(500) COMMENT '描述'")
    private String noticeDesc;
 
    @Column(name = "resultText", columnDefinition = "text COMMENT '返回结果'")
    private String resultText;
}

注： 使用了lombok的@Data注解自动生成get和set方法

4.持久层接口

import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.PagingAndSortingRepository;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;
 
/**
 * @Author: 爱飘de小子  10:48
 * @Date: 2018年09月10日 10点48分
 */
@Repository
public interface NoticeRepository extends PagingAndSortingRepository<Notice, Long>, JpaSpecificationExecutor<Notice> {
 
    /**
     * hql
     */
    @Query(value = " from Notice n where n.orderNo = :orderNo ")
    NoticeHisResult findByorderNo(@Param("orderNo") String orderNo);
 
    /**
     * sql
     */
    @Query(value = " select * from notice n where n.orderNo = :orderNo "，nativeQuery = true)
    NoticeHisResult findByorderNo(@Param("orderNo") String orderNo);
 
}

注：
1.继承PagingAndSortingRepository 实现分页和排序 和基础增删改查
2.继承JpaSpecificationExecutor 操作复杂sql或者动态sql（上篇文档有具体详解）

5.关于jpa需要注意的地方

1.原生sql更新操作：

   /**
     * 原生SQL实现更新方法接口
     */
    @Modifying
    @Query(value = "update notice set notice_desc = :name where id = :id ", nativeQuery = true)
    void updateOne(String noticeDesc,int id);

调用updateOne接口的方法上需要加上 @Transactional注解