JTS Geometry用例分析

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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.); 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.)"); 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.,119.32488 31.)"); 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：

 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

 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 
  
    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 
   
     points1 = new ArrayList 
    
      (); 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 
     
       points2 = new ArrayList 
      
        (); 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) } }