/* * Copyright 2015-2020 52°North Initiative for Geospatial Open Source * Software GmbH * * 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.n52.svalbard.encode.json; import org.n52.svalbard.coding.json.JSONConstants; import com.fasterxml.jackson.databind.node.ArrayNode; import com.fasterxml.jackson.databind.node.JsonNodeFactory; import com.fasterxml.jackson.databind.node.ObjectNode; import com.google.common.base.Preconditions; import org.locationtech.jts.geom.Coordinate; import org.locationtech.jts.geom.CoordinateSequence; import org.locationtech.jts.geom.Geometry; import org.locationtech.jts.geom.GeometryCollection; import org.locationtech.jts.geom.LineString; 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; /** * TODO JavaDoc * * @author Christian Autermann * * @since 1.0.0 */ public class GeoJSONEncoder extends JSONEncoder<Geometry> { public static final int DEFAULT_SRID = 4326; public static final String SRID_LINK_PREFIX = "http://www.opengis.net/def/crs/EPSG/0/"; private final JsonNodeFactory jsonFactory = JsonNodeFactory.withExactBigDecimals(false); public GeoJSONEncoder() { super(Geometry.class); } @Override public ObjectNode encodeJSON(Geometry value) throws JSONEncodingException { if (value == null) { return null; } else { return encodeGeometry(value, DEFAULT_SRID); } } protected ObjectNode encodeGeometry(Geometry geometry, int parentSrid) throws JSONEncodingException { Preconditions.checkNotNull(geometry); if (geometry.isEmpty()) { return null; } else if (geometry instanceof Point) { return encode((Point) geometry, parentSrid); } else if (geometry instanceof LineString) { return encode((LineString) geometry, parentSrid); } else if (geometry instanceof Polygon) { return encode((Polygon) geometry, parentSrid); } else if (geometry instanceof MultiPoint) { return encode((MultiPoint) geometry, parentSrid); } else if (geometry instanceof MultiLineString) { return encode((MultiLineString) geometry, parentSrid); } else if (geometry instanceof MultiPolygon) { return encode((MultiPolygon) geometry, parentSrid); } else if (geometry instanceof GeometryCollection) { return encode((GeometryCollection) geometry, parentSrid); } else { throw new JSONEncodingException("unknown geometry type " + geometry.getGeometryType()); } } protected ObjectNode encode(Point geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); json.put(JSONConstants.TYPE, JSONConstants.POINT); json.set(JSONConstants.COORDINATES, encodeCoordinates(geometry)); encodeCRS(json, geometry, parentSrid); return json; } protected ObjectNode encode(LineString geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); json.put(JSONConstants.TYPE, JSONConstants.LINE_STRING).set(JSONConstants.COORDINATES, encodeCoordinates(geometry)); encodeCRS(json, geometry, parentSrid); return json; } protected ObjectNode encode(Polygon geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); json.put(JSONConstants.TYPE, JSONConstants.POLYGON).set(JSONConstants.COORDINATES, encodeCoordinates(geometry)); encodeCRS(json, geometry, parentSrid); return json; } protected ObjectNode encode(MultiPoint geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); ArrayNode list = json.put(JSONConstants.TYPE, JSONConstants.MULTI_POINT).putArray(JSONConstants.COORDINATES); for (int i = 0; i < geometry.getNumGeometries(); ++i) { list.add(encodeCoordinates((Point) geometry.getGeometryN(i))); } encodeCRS(json, geometry, parentSrid); return json; } protected ObjectNode encode(MultiLineString geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); ArrayNode list = json.put(JSONConstants.TYPE, JSONConstants.MULTI_LINE_STRING).putArray(JSONConstants.COORDINATES); for (int i = 0; i < geometry.getNumGeometries(); ++i) { list.add(encodeCoordinates((LineString) geometry.getGeometryN(i))); } encodeCRS(json, geometry, parentSrid); return json; } protected ObjectNode encode(MultiPolygon geometry, int parentSrid) { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); ArrayNode list = json.put(JSONConstants.TYPE, JSONConstants.MULTI_POLYGON).putArray(JSONConstants.COORDINATES); for (int i = 0; i < geometry.getNumGeometries(); ++i) { list.add(encodeCoordinates((Polygon) geometry.getGeometryN(i))); } encodeCRS(json, geometry, parentSrid); return json; } public ObjectNode encode(GeometryCollection geometry, int parentSrid) throws JSONEncodingException { Preconditions.checkNotNull(geometry); ObjectNode json = jsonFactory.objectNode(); ArrayNode geometries = json.put(JSONConstants.TYPE, JSONConstants.GEOMETRY_COLLECTION).putArray(JSONConstants.GEOMETRIES); int srid = encodeCRS(json, geometry, parentSrid); for (int i = 0; i < geometry.getNumGeometries(); ++i) { geometries.add(encodeGeometry(geometry.getGeometryN(i), srid)); } return json; } protected ArrayNode encodeCoordinate(Coordinate coordinate) { ArrayNode array = jsonFactory.arrayNode().add(coordinate.getX()).add(coordinate.getY()); if (!Double.isNaN(coordinate.getZ())) { array.add(coordinate.getZ()); } return array; } protected ArrayNode encodeCoordinates(CoordinateSequence coordinates) { ArrayNode list = jsonFactory.arrayNode(); for (int i = 0; i < coordinates.size(); ++i) { list.add(encodeCoordinate(coordinates.getCoordinate(i))); } return list; } protected ArrayNode encodeCoordinates(Point geometry) { return encodeCoordinate(geometry.getCoordinate()); } protected ArrayNode encodeCoordinates(LineString geometry) { return encodeCoordinates(geometry.getCoordinateSequence()); } protected ArrayNode encodeCoordinates(Polygon geometry) { ArrayNode list = jsonFactory.arrayNode(); list.add(encodeCoordinates(geometry.getExteriorRing())); for (int i = 0; i < geometry.getNumInteriorRing(); ++i) { list.add(encodeCoordinates(geometry.getInteriorRingN(i))); } return list; } protected int encodeCRS(ObjectNode json, Geometry geometry, int parentSrid) { return encodeCRS(geometry.getSRID(), parentSrid, json); } protected int encodeCRS(int srid, int parentSrid, ObjectNode json) { if (srid == parentSrid || srid == 0 || (parentSrid == DEFAULT_SRID && srid == DEFAULT_SRID)) { return parentSrid; } else { json.putObject(JSONConstants.CRS).put(JSONConstants.TYPE, JSONConstants.LINK) .putObject(JSONConstants.PROPERTIES).put(JSONConstants.HREF, SRID_LINK_PREFIX + srid); return srid; } } }