@Override
public void setNonNullParameter(PreparedStatement ps, int i, String parameter, JdbcType jdbcType) throws SQLException {
PGgeometry pGgeometry = new PGgeometry(parameter);
Geometry geometry = pGgeometry.getGeometry();
geometry.setSrid(4326);
ps.setObject(i, pGgeometry);
}
@Override
public String getNullableResult(ResultSet rs, String columnName) throws SQLException {
String string = rs.getString(columnName);
return getResult(string);
}
@Override
public String getNullableResult(ResultSet rs, int columnIndex) throws SQLException {
String string = rs.getString(columnIndex);
return getResult(string);
}
@Override
public String getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {
String string = cs.getString(columnIndex);
return getResult(string);
}
private String getResult(String string) throws SQLException {
PGgeometry pGgeometry = new PGgeometry(string);
String s = pGgeometry.toString();
return s.replace("SRID=4326;", "");
}
}
注意，在getResult()中关于4326坐标系的定义，可以根据需要进行废弃。这里写上为了统一投影坐标系。
### 三、在数据中创建表，建表语句如下：
create table biz_point_test( id int8 primary key, name varchar(100), geom geometry(Point,4326) );
### 四、定义Mybatis-plus实体
package com.hngtghy.project.extend.student.domain;
import com.baomidou.mybatisplus.annotation.TableField; import com.baomidou.mybatisplus.annotation.TableId; import com.baomidou.mybatisplus.annotation.TableName; import com.hngtghy.framework.handler.PgGeometryTypeHandler;
import lombok.AllArgsConstructor; import lombok.Getter; import lombok.NoArgsConstructor; import lombok.Setter; import lombok.ToString;
@TableName(value ="biz_point_test",autoResultMap = true) @NoArgsConstructor @AllArgsConstructor @Setter @Getter @ToString public class PointTest {
@TableId
private Long id;
private String name;
@TableField(typeHandler = PgGeometryTypeHandler.class)
private String geom;
@TableField(exist=false)
private String geomJson;
}
提醒：1、在属性上使用@TableField(typeHandler=xxx)来指定对应的类型转换器。2、需要在实体上定义autoResultMap=true。否则配置不一定生效。
### 五、定义mapper查询器
package com.hngtghy.project.extend.student.mapper;
import org.apache.ibatis.annotations.Param; import org.apache.ibatis.annotations.Select;
import com.baomidou.mybatisplus.core.mapper.BaseMapper; import com.hngtghy.project.extend.student.domain.PointTest;
public interface PointTestMapper extends BaseMapper{
static final String FIND_GEOJSON_SQL="<script>"
+ "select st_asgeojson(geom) as geomJson from biz_point_test "
+ "where id = #{id} "
+ "<if test='null != name'>and p.name like concat('%', #{name}, '%')</if>"
+ "</script>";
@Select(FIND_GEOJSON_SQL)
PointTest findGeoJsonById(@Param("id")Long id,@Param("name")String name);
}
### 六、定义service业务类
package com.hngtghy.project.extend.student.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper; import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl; import com.hngtghy.project.extend.student.domain.PointTest; import com.hngtghy.project.extend.student.mapper.PointTestMapper; import com.hngtghy.project.extend.student.service.IPointTestService;
@Service public class PointTestServcieImpl extends ServiceImpl<PointTestMapper, PointTest> implements IPointTestService{
@Autowired
private PointTestMapper pointMapper;
@Override
public PointTest selectById(Long id) {
return pointMapper.selectById(id);
}
@Override
public List<PointTest> selectList(PointTest point) {
QueryWrapper<PointTest> queryWrapper = new QueryWrapper<PointTest>();
queryWrapper.select("id,name");
return this.getBaseMapper().selectList(queryWrapper);
}
@Override
public int insertPointTest(PointTest point) {
return pointMapper.insert(point);
}
@Override
public int updatePoint(PointTest point) {
return pointMapper.updateById(point);
}
@Override
public PointTest selectGeomById(Long id) {
QueryWrapper<PointTest> queryWrapper = new QueryWrapper<PointTest>();
queryWrapper.select("geom","st_asgeojson(geom) as geomJson");
queryWrapper.eq("id", id);
return this.getBaseMapper().selectOne(queryWrapper);
}
@Override
public PointTest findGeoJsonById(Long id) {
return pointMapper.findGeoJsonById(id, null);
}
}
这里添加了一个数据库不存在的字段geomJson,会将空间属性转变成geojson字段，方便于前台的如leaflet、openlayers、cesium等组件进行展示。所以使用postgis的st\_asgeojson（xxx）进行函数转换。
**七、相关方法调用**
//1、列表查询List pointList = pointService.selectList(null);System.out.println(pointList); [PointTest(id=1559371184090423297, name=中寨居委会, geom=null, geomJson=null), PointTest(id=2, name=禾滩村, geom=null, geomJson=null), PointTest(id=1559403683801796610, name=中寨居委会, geom=null, geomJson=null)] //2、插入PointTest point = new PointTest();point.setName("中寨居委会");point.setGeom("POINT(109.262605 27.200669)");//POINT(lng,lat) 经度,纬度pointService.insertPointTest(point); //3、查询数据 PointTest point = pointService.selectGeomById(1559371184090423297L); PointTest json = pointService.findGeoJsonById(1559371184090423297L); PointTest(id=null, name=null, geom=POINT(109.262605 27.200669), geomJson={"type":"Point","coordinates":[109.262605,27.200669]})PointTest(id=null, name=null, geom=null, geomJson={"type":"Point","coordinates":[109.262605,27.200669]})
### 八、使用pgadmin可以查看到相应的点数据，如下图所示：
 总结：通过以上步骤可以实现在mybatis-plus中操作geometry空间字段，同时实现查询和插入操作。通过geojson，结合前端可视化组件即可完成矢量数据的空间可视化。希望本文可以帮到你，欢迎交流。
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