JTS Geometry用例分析

港控/mmm° 2021-09-21 03:14 821阅读 0赞

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拓扑关系

## ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE4Mjk4NDM5_size_16_color_FFFFFF_t_70][]            **GeometryTest** ##

import com.vividsolutions.jts.geom.Coordinate;
    import com.vividsolutions.jts.geom.Geometry;
    import com.vividsolutions.jts.geom.GeometryCollection;
    import com.vividsolutions.jts.geom.GeometryFactory;
    import com.vividsolutions.jts.geom.LineString;
    import com.vividsolutions.jts.geom.LinearRing;
    import com.vividsolutions.jts.geom.Point;
    import com.vividsolutions.jts.geom.Polygon;
    import com.vividsolutions.jts.geom.MultiPolygon;
    import com.vividsolutions.jts.geom.MultiLineString;
    import com.vividsolutions.jts.geom.MultiPoint;
    import com.vividsolutions.jts.io.ParseException;
    import com.vividsolutions.jts.io.WKTReader;
     
     
    public class GeometryTest {
     
        private GeometryFactory geometryFactory = new GeometryFactory();
     
        /**
         * create a point
         * @return
         */
        public Point createPoint(){
            Coordinate coord = new Coordinate(109.013388, 32.715519);
            Point point = geometryFactory.createPoint( coord );
            return point;
        }
        
        /**
         * create a point by WKT
         * @return
         * @throws ParseException 
         */
        public Point createPointByWKT() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            Point point = (Point) reader.read("POINT (109.013388 32.715519)");
            return point;
        }
        
        /**
         * create multiPoint by wkt
         * @return
         */
        public MultiPoint createMulPointByWKT()throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            MultiPoint mpoint = (MultiPoint) reader.read("MULTIPOINT(109.013388 32.715519,119.32488 31.435678)");
            return mpoint;
        }
        /**
         * 
         * create a line
         * @return
         */
        public LineString createLine(){
            Coordinate[] coords  = new Coordinate[] {new Coordinate(2, 2), new Coordinate(2, 2)};
            LineString line = geometryFactory.createLineString(coords);
            return line;
        }
        
        /**
         * create a line by WKT
         * @return
         * @throws ParseException
         */
        public LineString createLineByWKT() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            LineString line = (LineString) reader.read("LINESTRING(0 0, 2 0)");
            return line;
        }
        
        /**
         * create multiLine 
         * @return
         */
        public MultiLineString createMLine(){
            Coordinate[] coords1  = new Coordinate[] {new Coordinate(2, 2), new Coordinate(2, 2)};
            LineString line1 = geometryFactory.createLineString(coords1);
            Coordinate[] coords2  = new Coordinate[] {new Coordinate(2, 2), new Coordinate(2, 2)};
            LineString line2 = geometryFactory.createLineString(coords2);
            LineString[] lineStrings = new LineString[2];
            lineStrings[0]= line1;
            lineStrings[1] = line2;
            MultiLineString ms = geometryFactory.createMultiLineString(lineStrings);
            return ms;
        }
        
        /**
         * create multiLine by WKT
         * @return
         * @throws ParseException
         */
        public MultiLineString createMLineByWKT()throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            MultiLineString line = (MultiLineString) reader.read("MULTILINESTRING((0 0, 2 0),(1 1,2 2))");
            return line;
        }
        
        /**
         * create a polygon(多边形) by WKT
         * @return
         * @throws ParseException
         */
        public Polygon createPolygonByWKT() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            Polygon polygon = (Polygon) reader.read("POLYGON((20 10, 30 0, 40 10, 30 20, 20 10))");
            return polygon;
        }
        
        /**
         * create multi polygon by wkt
         * @return
         * @throws ParseException
         */
        public MultiPolygon createMulPolygonByWKT() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            MultiPolygon mpolygon = (MultiPolygon) reader.read("MULTIPOLYGON(((40 10, 30 0, 40 10, 30 20, 40 10),(30 10, 30 0, 40 10, 30 20, 30 10)))");
            return mpolygon;
        }
        
        /**
         * create GeometryCollection  contain point or multiPoint or line or multiLine or polygon or multiPolygon
         * @return
         * @throws ParseException
         */
        public GeometryCollection createGeoCollect() throws ParseException{
            LineString line = createLine();
            Polygon poly =  createPolygonByWKT();
            Geometry g1 = geometryFactory.createGeometry(line);
            Geometry g2 = geometryFactory.createGeometry(poly);
            Geometry[] garray = new Geometry[]{g1,g2};
            GeometryCollection gc = geometryFactory.createGeometryCollection(garray);
            return gc;
        }
        
        /**
         * create a Circle  创建一个圆，圆心(x,y) 半径RADIUS
         * @param x
         * @param y
         * @param RADIUS
         * @return
         */
        public Polygon createCircle(double x, double y, final double RADIUS){
            final int SIDES = 32;//圆上面的点个数
            Coordinate coords[] = new Coordinate[SIDES+1];
            for( int i = 0; i < SIDES; i++){
                double angle = ((double) i / (double) SIDES) * Math.PI * 2.0;
                double dx = Math.cos( angle ) * RADIUS;
                double dy = Math.sin( angle ) * RADIUS;
                coords[i] = new Coordinate( (double) x + dx, (double) y + dy );
            }
            coords[SIDES] = coords[0];
            LinearRing ring = geometryFactory.createLinearRing( coords );
            Polygon polygon = geometryFactory.createPolygon( ring, null );
            return polygon;
        }
        /**
         * @param args
         * @throws ParseException 
         */
        public static void main(String[] args) throws ParseException {
            GeometryDemo gt = new GeometryDemo();
            Polygon p = gt.createCircle(0, 1, 2);
            //圆上所有的坐标(32个)
            Coordinate coords[] = p.getCoordinates();
            for(Coordinate coord:coords){
                System.out.println(coord.x+","+coord.y);
            }
        }
    }

Geometry之间的关系有下述几种：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE4Mjk4NDM5_size_16_color_FFFFFF_t_70 1][]

import com.vividsolutions.jts.geom.*;
    import com.vividsolutions.jts.io.ParseException;
    import com.vividsolutions.jts.io.WKTReader;
     
    /**
     * gemotry之间的关系使用
     */
    public class GeometryTest {
     
        private GeometryFactory geometryFactory = new GeometryFactory();
        
        /**
         *  两个几何对象是否是重叠的
         * @return
         * @throws ParseException
         */
        public boolean equalsGeo() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            LineString geometry1 = (LineString) reader.read("LINESTRING(0 0, 2 0, 5 0)");
            LineString geometry2 = (LineString) reader.read("LINESTRING(5 0, 0 0)");
            return geometry1.equals(geometry2);//true
        }
        
        /**
         * 几何对象没有交点(相邻)
         * @return
         * @throws ParseException
         */
        public boolean disjointGeo() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            LineString geometry1 = (LineString) reader.read("LINESTRING(0 0, 2 0, 5 0)");
            LineString geometry2 = (LineString) reader.read("LINESTRING(0 1, 0 2)");
            return geometry1.disjoint(geometry2);
        }
        
        /**
         * 至少一个公共点(相交)
         * @return
         * @throws ParseException
         */
        public boolean intersectsGeo() throws ParseException{
            WKTReader reader = new WKTReader( geometryFactory );
            LineString geometry1 = (LineString) reader.read("LINESTRING(0 0, 2 0, 5 0)");
            LineString geometry2 = (LineString) reader.read("LINESTRING(0 0, 0 2)");
            Geometry interPoint = geometry1.intersection(geometry2);//相交点
            System.out.println(interPoint.toText());//输出 POINT (0 0)
            return geometry1.intersects(geometry2);
        }
     
        /**
         * 判断以x,y为坐标的点point(x,y)是否在geometry表示的Polygon中
         * @param x
         * @param y
         * @param geometry wkt格式
         * @return
         */
        public boolean withinGeo(double x,double y,String geometry) throws ParseException {
     
            Coordinate coord = new Coordinate(x,y);
            Point point = geometryFactory.createPoint( coord );
     
            WKTReader reader = new WKTReader( geometryFactory );
            Polygon polygon = (Polygon) reader.read(geometry);
            return point.within(polygon);
        }
        /**
         * @param args
         * @throws ParseException 
         */
        public static void main(String[] args) throws ParseException {
            GeometryRelated gr = new GeometryRelated();
            System.out.println(gr.equalsGeo());
            System.out.println(gr.disjointGeo());
            System.out.println(gr.intersectsGeo());
            System.out.println(gr.withinGeo(5,5,"POLYGON((0 0, 10 0, 10 10, 0 10,0 0))"));
        }
     
    }

关系类型

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE4Mjk4NDM5_size_16_color_FFFFFF_t_70 2][]

import java.util.ArrayList;
    import java.util.List;
     
    import com.vividsolutions.jts.geom.Coordinate;
    import com.vividsolutions.jts.geom.Geometry;
    import com.vividsolutions.jts.geom.GeometryFactory;
    import com.vividsolutions.jts.geom.LineString;
     
    
    
    public class GeometryTest {
     
        private GeometryFactory geometryFactory = new GeometryFactory();
     
        /**
         * create a Point
         *
         * @param x
         * @param y
         * @return
         */
        public Coordinate point(double x, double y) {
            return new Coordinate(x, y);
        }
     
     
        /**
         * create a line
         *
         * @return
         */
        public LineString createLine(List<Coordinate> points) {
            Coordinate[] coords = (Coordinate[]) points.toArray(new Coordinate[points.size()]);
            LineString line = geometryFactory.createLineString(coords);
            return line;
        }
     
        /**
         * 返回a指定距离内的多边形和多多边形
         *
         * @param a
         * @param distance
         * @return
         */
        public Geometry bufferGeo(Geometry a, double distance) {
            return a.buffer(distance);
        }
     
        /**
         * 返回(A)与(B)中距离最近的两个点的距离
         *
         * @param a
         * @param b
         * @return
         */
        public double distanceGeo(Geometry a, Geometry b) {
            return a.distance(b);
        }
     
        /**
         * 两个几何对象的交集
         *
         * @param a
         * @param b
         * @return
         */
        public Geometry intersectionGeo(Geometry a, Geometry b) {
            return a.intersection(b);
        }
     
        /**
         * 几何对象合并
         *
         * @param a
         * @param b
         * @return
         */
        public Geometry unionGeo(Geometry a, Geometry b) {
            return a.union(b);
        }
     
        /**
         * 在A几何对象中有的，但是B几何对象中没有
         *
         * @param a
         * @param b
         * @return
         */
        public Geometry differenceGeo(Geometry a, Geometry b) {
            return a.difference(b);
        }
     
     
        public static void main(String[] args) {
            Operation op = new Operation();
            //创建一条线
            List<Coordinate> points1 = new ArrayList<Coordinate>();
            points1.add(op.point(0, 0));
            points1.add(op.point(1, 3));
            points1.add(op.point(2, 3));
            LineString line1 = op.createLine(points1);
            //创建第二条线
            List<Coordinate> points2 = new ArrayList<Coordinate>();
            points2.add(op.point(3, 0));
            points2.add(op.point(3, 3));
            points2.add(op.point(5, 6));
            LineString line2 = op.createLine(points2);
     
            System.out.println(op.distanceGeo(line1, line2));//out 1.0
            System.out.println(op.intersectionGeo(line1, line2));//out GEOMETRYCOLLECTION EMPTY
            System.out.println(op.unionGeo(line1, line2)); //out MULTILINESTRING ((0 0, 1 3, 2 3), (3 0, 3 3, 5 6))
            System.out.println(op.differenceGeo(line1, line2));//out LINESTRING (0 0, 1 3, 2 3)
        }
    }

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