GeomBuilder.java
/* Copyright 2013 The jeo project. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.locationtech.spatial4j.util;
import java.lang.reflect.Array;
import java.util.ArrayDeque;
import java.util.Arrays;
import java.util.Deque;
import java.util.Iterator;
import java.util.Locale;
import org.locationtech.jts.geom.Coordinate;
import org.locationtech.jts.geom.Geometry;
import org.locationtech.jts.geom.GeometryCollection;
import org.locationtech.jts.geom.GeometryFactory;
import org.locationtech.jts.geom.LineString;
import org.locationtech.jts.geom.LinearRing;
import org.locationtech.jts.geom.MultiLineString;
import org.locationtech.jts.geom.MultiPoint;
import org.locationtech.jts.geom.MultiPolygon;
import org.locationtech.jts.geom.Point;
import org.locationtech.jts.geom.Polygon;
import org.locationtech.jts.geom.PrecisionModel;
/**
* Builder for geometry objects.
* <p>
* Example usage:
* <pre><code>
* GeometryBuilder gb = new GeometryBuilder();
*
* // create array two 2d points and turn into a line string
* gb.points(1,2,3,4,5,6).toLineString();
*
* // build a polygon with holes
* gb.points(0,0,10,0,10,10,0,10,0,0).ring()
* .points(4,4,6,4,6,6,4,6,4,4).ring()
* .toPolygon();
*
* </code></pre>
* </p>
*
* <p>
* Class taken from http://github.com/jeo/jeo, Nov 2017 by Justin Deoliveira.
* </p>
*
* @author Justin Deoliveira, OpenGeo
*
*/
public class GeomBuilder {
GeometryFactory factory;
Deque<Coordinate> cstack = new ArrayDeque<>();
Deque<Geometry> gstack = new ArrayDeque<>();
/**
* Constructs a builder with the default geometry factory.
*/
public GeomBuilder() {
this(new GeometryFactory());
}
/**
* Constructs a builder with an explicit geometry factory.
*/
public GeomBuilder(GeometryFactory factory) {
this.factory = factory;
}
/**
* Constructs a builder with a specific srid for geometry objects.
*/
public GeomBuilder(int srid) {
this.factory = new GeometryFactory(new PrecisionModel(), srid);
}
/**
* Adds a 2d point to the coordinate stack.
*/
public GeomBuilder point(double x, double y) {
cstack.push(new Coordinate(x, y));
return this;
}
/**
* Adds a 3d point to the coordinate stack.
*/
public GeomBuilder pointz(double x, double y, double z) {
cstack.push(new Coordinate(x,y,z));
return this;
}
/**
* Adds an array of 2d points to the coordinate stack.
*/
public GeomBuilder points(double ...ord) {
if (ord.length % 2 != 0) {
throw new IllegalArgumentException("Must specify even number of ordinates");
}
for (int i = 0; i < ord.length; i +=2 ) {
point(ord[i], ord[i+1]);
}
return this;
}
/**
* Adds an array of 3d points to the coordinate stack.
*/
public GeomBuilder pointsz(double ...ord) {
if (ord.length % 3 != 0) {
throw new IllegalArgumentException("Must specify ordinates as triples");
}
for (int i = 0; i < ord.length; i +=3 ) {
pointz(ord[i], ord[i+1], ord[i+2] );
}
return this;
}
/**
* Creates a Point from the last point on the coordinate stack, and places the result
* on the geometry stack.
*/
public GeomBuilder point() {
gstack.push(factory.createPoint(cpop()));
return this;
}
/**
* Creates a LineString from all points on the coordinate stack, and places the result
* on the geometry stack.
*/
public GeomBuilder lineString() {
gstack.push(factory.createLineString(cpopAll()));
return this;
}
/**
* Creates a LinearRing from all points on the coordinate stack, and places the result
* on the geometry stack.
* <p>
* If the first and last coordinate on the point stack are not equal an additional point
* will be added.
* </p>
*/
public GeomBuilder ring() {
Coordinate[] coords = cpopAll();
if (coords.length > 1 && !coords[0].equals(coords[coords.length-1])) {
Coordinate[] tmp = new Coordinate[coords.length+1];
System.arraycopy(coords, 0, tmp, 0, coords.length);
tmp[tmp.length-1] = new Coordinate(tmp[0]);
coords = tmp;
}
gstack.push(factory.createLinearRing(coords));
return this;
}
/**
* Creates a Polygon from all LinearRings on the geometry stack and places the result back
* on the geometry stack.
*/
public GeomBuilder polygon() {
if (gstack.isEmpty() || !(gstack.peek() instanceof LinearRing)) {
ring();
}
LinearRing[] rings = gpopAll(LinearRing.class);
LinearRing outer = rings[0];
LinearRing[] inner = null;
if (rings.length > 1) {
inner = Arrays.copyOfRange(rings, 1, rings.length);
}
gstack.push(factory.createPolygon(outer, inner));
return this;
}
/**
* Creates a MultiPoint from all coordinates on the coordinate stack, plaching the result
* back on the geometry stack.
* <p>
* If the coordinate stack is empty this method will consume all Point geometries on
* the geometry stack.
* </p>
*/
public GeomBuilder multiPoint() {
if (!cstack.isEmpty()) {
gstack.push(factory.createMultiPoint(cpopAll()));
}
else {
gstack.push(factory.createMultiPoint(gpopAll(Point.class)));
}
return this;
}
/**
* Creates a MultiLineString from all LineStrings on the geometry stack and places the result
* back on the geometry stack.
*/
public GeomBuilder multiLineString() {
gstack.push(factory.createMultiLineString(gpopAll(LineString.class)));
return this;
}
/**
* Creates a MultiPolygon from all Polygons on the geometry stack and places the result
* back on the geometry stack.
*/
public GeomBuilder multiPolygon() {
gstack.push(factory.createMultiPolygon(gpopAll(Polygon.class)));
return this;
}
/**
* Creates a GeometryCollection from all Geometries on the geometry stack and places the result
* back on the geometry stack.
*/
public GeomBuilder collection() {
gstack.push(factory.createGeometryCollection(gpopAll(Geometry.class)));
return this;
}
/**
* Buffers the geometry at the top of the geometry stack, and places the result back on the
* geometry stack.
*/
public GeomBuilder buffer(double amt) {
gstack.push(gpop(Geometry.class).buffer(amt));
return this;
}
/**
* Consumes the top of the geometry stack.
*/
public Geometry get() {
return gpop(Geometry.class);
}
/**
* Builds and returns a Point.
* <p>
* This method is equivalent to:
* <pre>
* (Point) point().get();
* </pre>
* </p>
*/
public Point toPoint() {
return point().gpop(Point.class);
}
/**
* Builds and returns a LineString.
* <p>
* This method is equivalent to:
* <pre>
* (LineString) lineString().get();
* </pre>
* </p>
*/
public LineString toLineString() {
return lineString().gpop(LineString.class);
}
/**
* Builds and returns a LineString.
* <p>
* This method is equivalent to:
* <pre>
* (LinearRing) ring().get();
* </pre>
* </p>
*/
public LinearRing toLinearRing() {
return ring().gpop(LinearRing.class);
}
/**
* Builds and returns a Polygon.
* <p>
* This method is equivalent to:
* <pre>
* (Polygon) polygon().get();
* </pre>
* </p>
*/
public Polygon toPolygon() {
return polygon().gpop(Polygon.class);
}
/**
* Builds and returns a MultiPoint.
* <p>
* This method is equivalent to:
* <pre>
* (MultiPoint) multiPoint().get();
* </pre>
* </p>
*/
public MultiPoint toMultiPoint() {
return multiPoint().gpop(MultiPoint.class);
}
/**
* Builds and returns a MultiLineString.
* <p>
* This method is equivalent to:
* <pre>
* (MultiLineString) multiLineString().get();
* </pre>
* </p>
*/
public MultiLineString toMultiLineString() {
return multiLineString().gpop(MultiLineString.class);
}
/**
* Builds and returns a MultiPolygon.
* <p>
* This method is equivalent to:
* <pre>
* (MultiPolygon) multiPolygon().get();
* </pre>
* </p>
*/
public MultiPolygon toMultiPolygon() {
return multiPolygon().gpop(MultiPolygon.class);
}
/**
* Builds and returns a GEometryCollection.
* <p>
* This method is equivalent to:
* <pre>
* (GeometryCollection) collection().get();
* </pre>
* </p>
*/
public GeometryCollection toCollection() {
return collection().gpop(GeometryCollection.class);
}
Coordinate cpop() {
return cpop(1)[0];
}
Coordinate[] cpop(int n) {
if (cstack.size() < n) {
throw new IllegalStateException(String.format(Locale.ROOT,"Expected %d values on coordinate stack, "
+ "but found %d", n, cstack.size()));
}
Coordinate[] c = new Coordinate[n];
for (int i = 0; i < n; i++) {
c[n-i-1] = cstack.pop();
}
return c;
}
Coordinate[] cpopAll() {
if (cstack.isEmpty()) {
throw new IllegalStateException("Coordinate stack is empty");
}
return cpop(cstack.size());
}
<T extends Geometry> T gpop(Class<T> clazz) {
return gpop(1, clazz)[0];
}
<T extends Geometry> T[] gpop(int n, Class<T> clazz) {
if (gstack.size() < n) {
throw new IllegalStateException(String.format(Locale.ROOT,"Expected %d values on geometry stack, "
+ "but found %d", n, gstack.size()));
}
@SuppressWarnings("unchecked") T[] l = (T[]) Array.newInstance(clazz, n);
for (int i = 0; i < n; i++) {
Geometry g = gstack.pop();
if (!clazz.isInstance(g)) {
throw new IllegalStateException(String.format(Locale.ROOT,"Expected %s on geometry stack, but "
+ "found %s", clazz.getSimpleName(), g.getClass().getSimpleName()));
}
l[n-i-1] = clazz.cast(g);
}
return l;
}
<T extends Geometry> T[] gpopAll(Class<T> clazz) {
if (gstack.isEmpty()) {
throw new IllegalArgumentException("Geometry stack is empty");
}
int n = 0;
Iterator<Geometry> it = gstack.iterator();
while (it.hasNext() && clazz.isInstance(it.next())) {
n++;
}
if (n == 0) {
throw new IllegalArgumentException(
String.format(Locale.ROOT,"Expected %s on geometry stack", clazz.getSimpleName()));
}
return gpop(n, clazz);
}
}