如何从 HibernateSpatial API 中的多边形对象数据类型更改几何对象数据类型？

Question

尝试使用 HibernateSpatial API 将多边形形状存储在数据库中。我已经关注this tutorial 来存储值。我使用 Mysql 作为我的数据库服务器。所以对我的场景做了一些改变。获取以下错误以将其存储在数据库中。

::错误::

错误 [org.hibernate.engine.jdbc.spi.SqlExceptionHelper] (http-/192.168.5.244:8080-1) 数据截断：无法从您发送到 GEOMETRY 字段的数据中获取几何对象

错误 [com.service.HibernateSaveService] (http-/192.168.5.244:8080-1) 异常:_: 无法执行语句

提示

我收到此错误，因为试图直接在几何数据类型中传递多边形（这是我的假设）。请帮助我解决此问题并帮助我将值存储在数据库中。

我的代码如下。

实体类:_:

package com.entity;

// Generated Mar 1, 2014 12:22:56 PM by Hibernate Tools 3.4.0.CR1

import static javax.persistence.GenerationType.IDENTITY;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
import javax.persistence.UniqueConstraint;

import org.hibernate.annotations.Type;

import com.vividsolutions.jts.geom.Polygon;

/**
 * HibernateSpatial generated by hbm2java
 */
@Entity
@Table(name = "HIBERNATE_SPATIAL", catalog = "geocodedb", uniqueConstraints = @UniqueConstraint(columnNames = "GEO_REGION_NAME"))
public class HibernateSpatialEntity implements java.io.Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private Integer prdGeoRegionId;
    private String geoRegionName;
    private String geoRegionDescription;

    @Type(type="org.hibernate.spatial.GeometryType")
    private Polygon geoRegionDefinition;

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "PRD_GEO_REGION_ID", unique = true, nullable = false)
    public Integer getPrdGeoRegionId() {
        return this.prdGeoRegionId;
    }

    public void setPrdGeoRegionId(Integer prdGeoRegionId) {
        this.prdGeoRegionId = prdGeoRegionId;
    }

    @Column(name = "GEO_REGION_NAME", unique = true, nullable = false, length = 50)
    public String getGeoRegionName() {
        return this.geoRegionName;
    }

    public void setGeoRegionName(String geoRegionName) {
        this.geoRegionName = geoRegionName;
    }

    @Column(name = "GEO_REGION_DESCRIPTION", length = 70)
    public String getGeoRegionDescription() {
        return this.geoRegionDescription;
    }

    public void setGeoRegionDescription(String geoRegionDescription) {
        this.geoRegionDescription = geoRegionDescription;
    }

    @Column(name = "GEO_REGION_DEFINITION")
    public Polygon getGeoRegionDefinition() {
        return this.geoRegionDefinition;
    }

    public void setGeoRegionDefinition(Polygon geoRegionDefinition) {
        this.geoRegionDefinition = geoRegionDefinition;
    }

}

坚持课程:_:

package com.service;

import java.util.Random;
import javax.ejb.Stateless;
import javax.ejb.TransactionManagement;
import javax.ejb.TransactionManagementType;
import javax.persistence.EntityManager;
import javax.persistence.Persistence;
import javax.ws.rs.Consumes;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;

import org.hibernate.Session;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.solartis.entity.HibernateSpatialEntity;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.Polygon;
import com.vividsolutions.jts.io.ParseException;
import com.vividsolutions.jts.io.WKTReader;

@Stateless
@TransactionManagement(TransactionManagementType.BEAN)
@Path("/")
public class HibernateSaveService {
    /**
     * mLogger - attribute used for to write the log
     */
    private static final Logger mLogger = LoggerFactory
            .getLogger(HibernateSaveService.class);

    @POST
    @Path("/saveHibernate")
    @Consumes("*/*")
    @Produces("*/*")
    public String saveShapes(String jsonRequest) {
        String statusResult =   null;
        String methodName = "saveShapes";
        StringBuilder regionName    =   null;
        Session session =   null;
        Random random   =   null;
        HibernateSpatialEntity hibernateEntity  =   null;
        Polygon poly    =   null;
        String singleShape  =   "Polygon((-50.123456789 -50.123456789,50.98765432175 -50.753951654852,50 50,-50 50,-50.123456789 -50.123456789))";

        mLogger.debug("Entered inside the Method :_: " + methodName );
        Geometry geom   =   wktToGeometry(singleShape);
        try {
            EntityManager entity = Persistence.createEntityManagerFactory(
                    "spatialPersistenceUnit").createEntityManager();
            session = (Session) entity.getDelegate();
            if (!geom.getGeometryType().equals("Polygon")) {
                throw new RuntimeException("Geometry must be a Polygon. Got a " + geom.getGeometryType());
            }
            else {
                //poly.
                mLogger.info("GeoType :_: " + geom.getGeometryType());
                hibernateEntity =   new HibernateSpatialEntity();
                random  =   new Random();
                hibernateEntity.setGeoRegionDefinition((Polygon)geom);
                hibernateEntity.setGeoRegionDescription("ABCDEFGHIJKLMNOPQRSTUVWXYZ");
                regionName  =   new StringBuilder();
                regionName.append("RegionName :_: ").append(random.nextInt(10000));
                hibernateEntity.setGeoRegionName(regionName.toString());
                mLogger.info("StoredName :_: " + regionName.toString());
                session.beginTransaction();
                session.save(hibernateEntity);
            }

        } catch(Exception exception) {
            mLogger.error("Exception :_: " + exception.getMessage());
        } finally {
            session.clear();
            if ((session != null) && (session.isOpen())) {
                session.close();
            }
        }
        mLogger.debug("Exited from the Method :_: " + methodName);
        return statusResult;
    }

    private Geometry wktToGeometry(String wktPoint) {
        WKTReader fromText = new WKTReader();
        Geometry geom = null;
        try {
            geom = fromText.read(wktPoint);
        } catch (ParseException e) {
            throw new RuntimeException("Not a WKT string:" + wktPoint);
        }
        return geom;
    }
}

数据库架构

+------------------------+--------------+------+-----+---------+----------------+
| Field                  | Type         | Null | Key | Default | Extra          |
+------------------------+--------------+------+-----+---------+----------------+
| PRD_GEO_REGION_ID      | int(11)      | NO   | PRI | NULL    | auto_increment |
| OWNER_ID               | decimal(3,0) | NO   |     | NULL    |                |
| GEO_REGION_NAME        | varchar(50)  | NO   | UNI | NULL    |                |
| GEO_REGION_DESCRIPTION | varchar(70)  | YES  |     | NULL    |                |
| GEO_REGION_DEFINITION  | geometry     | YES  |     | NULL    |                |
+------------------------+--------------+------+-----+---------+----------------+

问候， 阿伦拉杰。

Answer 1

通过将注释放在适当的位置解决了问题。

问题:_:

@Type(type="org.hibernate.spatial.GeometryType")
private Polygon geoRegionDefinition;

我在错误的地方指定了类型注释。那就是问题所在。这就是 JavaObject 无法将数据转换为 GeometryType 的原因。

解决方案:_:

只需将Type注解放在Entity Class的getter方法中即可。问题已解决。

@Type(type="org.hibernate.spatial.GeometryType")
@Column(name = "GEO_REGION_DEFINITION")
public Polygon getGeoRegionDefinition() {
    return this.geoRegionDefinition;
}

public void setGeoRegionDefinition(Polygon geoRegionDefinition) {
    this.geoRegionDefinition = geoRegionDefinition;
}