mybatisplus集成geometry实现增改功能

前言

在我们工作中想要实现将空间点位信息存储到数据库时,一般使用以下语句实现

INSERT INTO `test-point` ( point,text ) VALUES ( st_GeomFromText ( 'POINT(1 1)' ),'第1个点');

update `test-point` set point=st_PointFromText('POINT(5 5)') where id =10;

但是这样每次都要去编写新增与编辑的sql语句非常麻烦,体现不出mybatisplus的便捷性,所以可以增加GeometryTypeHandler在mybatisplus生成新增编辑语句时将st_GeomFromText ()函数拼接到sql语句上,更加方便快捷

一.准备工作

首先项目添加依赖:

<dependency><groupId>com.vividsolutions</groupId><artifactId>jts</artifactId><version>1.13</version>
</dependency>

在项目中加入GeometryTypeHandler

package com.sinosoft.springbootplus.lft.business.dispatch.map.common;import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;
import com.vividsolutions.jts.geom.PrecisionModel;
import com.vividsolutions.jts.io.*;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;@MappedTypes({String.class})
@MappedJdbcTypes({JdbcType.OTHER})
@Slf4j
public class GeometryTypeHandler extends BaseTypeHandler<String> {@Overridepublic void setNonNullParameter(PreparedStatement preparedStatement, int i, String s, JdbcType jdbcType) throws SQLException {try{//String转GeometryGeometry geo = new WKTReader(new GeometryFactory(new PrecisionModel())).read(s);// Geometry转WKBbyte[] geometryBytes = new WKBWriter(2, ByteOrderValues.LITTLE_ENDIAN, false).write(geo);// 设置SRID为mysql默认的 0byte[] wkb = new byte[geometryBytes.length+4];wkb[0] = wkb[1] = wkb[2] = wkb[3] = 0;System.arraycopy(geometryBytes, 0, wkb, 4, geometryBytes.length);preparedStatement.setBytes(i,wkb);}catch (ParseException e){log.error("坐标转换异常：【{}】",e.getMessage(),e);}}@Overridepublic String getNullableResult(ResultSet resultSet, String s){try(InputStream inputStream = resultSet.getBinaryStream(s)){Geometry geo = getGeometryFromInputStream(inputStream);if(geo != null){return geo.toString();}}catch(Exception e){log.error("坐标转换异常：【{}】",e.getMessage(),e);}return null;}@Overridepublic String getNullableResult(ResultSet resultSet, int i){try(InputStream inputStream = resultSet.getBinaryStream(i)){Geometry geo = getGeometryFromInputStream(inputStream);if(geo != null){return geo.toString();}}catch(Exception e){log.error("坐标转换异常：【{}】",e.getMessage(),e);}return null;}@Overridepublic String getNullableResult(CallableStatement callableStatement, int i) throws SQLException {return "";}/*** 流 转 geometry* */private  Geometry getGeometryFromInputStream(InputStream inputStream) throws Exception {Geometry dbGeometry = null;if (inputStream != null) {// 二进制流转成字节数组byte[] buffer = new byte[255];int bytesRead;ByteArrayOutputStream baos = new ByteArrayOutputStream();while ((bytesRead = inputStream.read(buffer)) != -1) {baos.write(buffer, 0, bytesRead);}// 得到字节数组byte[] geometryAsBytes = baos.toByteArray();// 字节数组小于5 异常if (geometryAsBytes.length < 5) {throw new RuntimeException("坐标异常");}//字节数组前4个字节表示srid 去掉byte[] sridBytes = new byte[4];System.arraycopy(geometryAsBytes, 0, sridBytes, 0, 4);boolean bigEndian = (geometryAsBytes[4] == 0x00);// 解析sridint srid = 0;if (bigEndian) {for (byte sridByte : sridBytes) {srid = (srid << 8) + (sridByte & 0xff);}} else {for (int i = 0; i < sridBytes.length; i++) {srid += (sridBytes[i] & 0xff) << (8 * i);}}WKBReader wkbReader = new WKBReader();// WKBReader 把字节数组转成geometry对象。byte[] wkb = new byte[geometryAsBytes.length - 4];System.arraycopy(geometryAsBytes, 4, wkb, 0, wkb.length);dbGeometry = wkbReader.read(wkb);dbGeometry.setSRID(srid);}return dbGeometry;}
}