GeoTools常见函数用法

GeoTools is an open source Java library that provides tools for geospatial data

参考网址：http://docs.geotools.org/stable/userguide/library/jts/geometry.html

maven引入geotools依赖

   <repositories>
        <repository>
            <id>osgeo</id>
            <name>Open Source Geospatial Foundation Repository</name>
            <url>http://download.osgeo.org/webdav/geotools/</url>
        </repository>
    </repositories>

        <dependency>
            <groupId>org.geotools</groupId>
            <artifactId>gt-main</artifactId>
            <version>23-SNAPSHOT</version>
            <exclusions>
                <exclusion>
                    <groupId>javax</groupId>
                    <artifactId>javaee-api</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

JTS创建点线面

#创建点
GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
Coordinate coord = new Coordinate(1, 1);
Point point = geometryFactory.createPoint(coord);

GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
WKTReader reader = new WKTReader(geometryFactory);
Point point = (Point) reader.read("POINT (1 1)");


#创建线
GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
Coordinate[] coords  = new Coordinate[] {new Coordinate(0, 2), new Coordinate(2, 0), new Coordinate(8, 6) };
LineString line = geometryFactory.createLineString(coordinates);

GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
WKTReader reader = new WKTReader(geometryFactory);
LineString line = (LineString) reader.read("LINESTRING(0 2, 2 0, 8 6)");


#创建面
GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory();
Coordinate[] coords  = new Coordinate[] {new Coordinate(4, 0), new Coordinate(2, 2), new Coordinate(4, 4), new Coordinate(6, 2), new Coordinate(4, 0) };
LinearRing ring = geometryFactory.createLinearRing(coords);
LinearRing holes[] = null; // use LinearRing[] to represent holes
Polygon polygon = geometryFactory.createPolygon(ring, holes);

GeometryFactory geometryFactory = JTSFactoryFinder.getGeometryFactory( null );
WKTReader reader = new WKTReader( geometryFactory );
Polygon polygon = (Polygon) reader.read("POLYGON((20 10, 30 0, 40 10, 30 20, 20 10))");

Geometry之间的空间关系

image.png

1、点面包含分析

用途：判断一个面是否包含一个点，即一个点是否在一个面内。点、面皆为wkt字符串格式。
关键代码：

              import org.geotools.geometry.jts.JTSFactoryFinder;
              import org.locationtech.jts.geom.Geometry;
              import org.locationtech.jts.io.ParseException;
              import org.locationtech.jts.io.WKTReader;

                WKTReader reader = new WKTReader(JTSFactoryFinder.getGeometryFactory());
                String wktPoly = polygon;
                Geometry poly = reader.read(wktPoly);

               String wktPoint = "POINT("+item.get("lng")+" "+item.get("lat")+")";
               Geometry point = reader.read(wktPoint);
               boolean flag = poly.contains(point);