Spring Data repository and native query with Geometry return type

Question

I'm creating a project that uses some spatial queries. I use Spring boot with spring data repositories and PostgreSQL with PostGIS extension as database.

I created this repository:

import com.vividsolutions.jts.geom.Geometry;
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.CrudRepository;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;

@Repository
public interface AreaRepository extends CrudRepository<Area, Long> {

    /*
      extra queries for Area here
    */

    @Query(value="select st_intersection(" +
                ":base_layer ," +
                ":filter_layer" +
                ")", nativeQuery = true)
    Geometry geometryIntersectGeometry(@Param("base_layer") Geometry baseGeometry,@Param("filter_layer") Geometry filterGeometry);

}

It contains some queries for the Area entity. I also want to use some PostGIS functions to do some calculations, so I created geometryIntersectGeometry to call the st_intersection function from PostGis, this should return a geometry.

I set the hibernate dialect to PostGIS in the settings:

spring.datasource.driverClassName=org.postgresql.Driver
spring.datasource.url=jdbc:postgresql://localhost:5432/test_db
spring.datasource.username=postgres
spring.datasource.password=postgres
spring.jpa.properties.hibernate.dialect = org.hibernate.spatial.dialect.postgis.PostgisDialect

And I have the dependencies for hibernate spatial:

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.postgresql</groupId>
            <artifactId>postgresql</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-spatial</artifactId>
            <version>${hibernate.version}</version>
        </dependency>
        ...

Calling the geometryIntersectGeometry function results in an error:

No Dialect mapping for JDBC type: 1111; nested exception is org.hibernate.MappingException: No Dialect mapping for JDBC type: 1111,{}

How do I tell JPA/Spring Data to map the geometry (PostGIS type) response to a Geometry(com.vividsolutions.jts.geom.Geometry) object?

Answer 1

Managed to fix it by writing a custom implementation of the repository and register the type (thx Simon Martinelli)

repository:

import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.CrudRepository;
import org.springframework.data.repository.query.Param;
import org.springframework.stereotype.Repository;

@Repository
public interface AreaRepository extends CrudRepository<Area, Long>, AreaGisRepository {

    /*
      extra queries for Area here
    */

}

interface:

import com.vividsolutions.jts.geom.Geometry;

public interface AreaGisRepository {

    Geometry geometryIntersectGeometry(Geometry baseGeometry, Geometry filterGeometry);
}

and implementation:

import com.vividsolutions.jts.geom.Geometry;
import org.hibernate.spatial.JTSGeometryType;
import org.hibernate.spatial.dialect.postgis.PGGeometryTypeDescriptor;
import org.springframework.beans.factory.annotation.Autowired;

import javax.persistence.EntityManager;

public class AreaGisRepositoryImpl implements AreaGisRepository {

    private EntityManager entityManager;

    @Autowired
    public AreaGisRepositoryImpl(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    @Override
    public Geometry geometryIntersectGeometry(Geometry baseGeometry, Geometry filterGeometry) {
        return (Geometry) entityManager
                .createNativeQuery(
                        "select st_intersection(:base_layer , :filter_layer) as geom")
                .setParameter("base_layer", baseGeometry)
                .setParameter("filter_layer", filterGeometry)
                .unwrap(org.hibernate.query.NativeQuery.class)
                .addScalar("geom", new JTSGeometryType(PGGeometryTypeDescriptor.INSTANCE))
                .getSingleResult();
    }

}

It works perfect, but I now have a hard coded dependency on Postgis (not likely we will use something else, but ...)