利用hibernate-spatial让Spring Data JPA支持空间数据

Spring Data JPA的极度简便的使用方式让我们爱不释手，但是我们在项目中经常会有使用空间数据的场景，而不同的数据库对空间数据实现的方式不同，而这些不仅是JPA或者Spring Data JPA都是不支持的这时我们需要引入hibernate-spatial来去除数据库支持的异构性。
在本例中集成了Spring Data JPA、hibernate -spatial、PostGIS一起的使用方式。

1. 添加依赖

<dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-spatial</artifactId>
    <version>5.2.10.Final</version>
</dependency>

2. 数据库方言指定

spring.jpa.database-platform: org.hibernate.spatial.dialect.postgis.PostgisPG9Dialect

org.hibernate.spatial.dialect下还有h2,mysql,oracle,sqlserver的方言。

3. 属性映射

 @Column(columnDefinition = "geometry(Point,4326)")
 private Point point;

4. 定义Spring Data Repository

public interface CityRepository extends JpaRepository<City,Long> {
    @Query("select city from City as city where equals(city.point,:point) = TRUE")
    List<City> findByPoint(@Param("point") Point point);
}

5. 保存测试

@Bean
CommandLineRunner geometrySave(CityRepository cityRepository){

    return e ->{
        City city = new City();
        city.setName("合肥");
        Geometry point = wktReader().read("POINT (117.2 31.8)");
        Point pointToSave = point.getInteriorPoint();
        pointToSave.setSRID(4326);
        city.setPoint(pointToSave);
        cityRepository.save(city);
    };

}

6. 读取测试

@Bean
CommandLineRunner geometryRead(CityRepository cityRepository){

    return e -> {
        City city = cityRepository.findOne(3l);
        Point point = city.getPoint();
        log.info("经度:" + point.getX() + " 维度:" + point.getY() + " 坐标系统:" + point.getSRID());
    };

}

7. 查询测试

@Bean
CommandLineRunner geometryQuery(CityRepository cityRepository){
    return e -> {
        Geometry point = wktReader().read("POINT (117.2 31.8)");
        Point pointToQuery = point.getInteriorPoint();
        pointToQuery.setSRID(4326);

        List<City> cities = cityRepository.findByPoint(pointToQuery);

        for (City city : cities) {
            log.info("查询结果为:" + city.getId() + "/" +city.getName() + "/" +city.getPoint());
        }

    };
}

我们在cityRepository中使用了hibernate-spatial中的空间函数equals，具体空间函数列表请查看
http://docs.jboss.org/hibernate/orm/5.2/userguide/html_single/Hibernate_User_Guide.html#spatial-configuration-dialect

8 源码地址

http://www.wisely.top/2017/06/26/hibernate-spatial-spring-data-jpa/