source: josm/trunk/src/org/openstreetmap/josm/io/GeoJSONReader.java@ 15735

Last change on this file since 15735 was 15684, checked in by Don-vip, 4 years ago

read GeoJson array properties as OSM tags
  • Property svn:eol-style set to native
File size: 14.3 KB
Line 
1// License: GPL. For details, see LICENSE file.
2package org.openstreetmap.josm.io;
3
4import static org.openstreetmap.josm.tools.I18n.tr;
5
6import java.io.InputStream;
7import java.util.List;
8import java.util.Map;
9import java.util.Objects;
10import java.util.Optional;
11import java.util.TreeMap;
12import java.util.stream.Collectors;
13
14import javax.json.Json;
15import javax.json.JsonArray;
16import javax.json.JsonNumber;
17import javax.json.JsonObject;
18import javax.json.JsonString;
19import javax.json.JsonValue;
20import javax.json.stream.JsonParser;
21import javax.json.stream.JsonParser.Event;
22import javax.json.stream.JsonParsingException;
23
24import org.openstreetmap.josm.data.coor.EastNorth;
25import org.openstreetmap.josm.data.coor.LatLon;
26import org.openstreetmap.josm.data.osm.DataSet;
27import org.openstreetmap.josm.data.osm.Node;
28import org.openstreetmap.josm.data.osm.OsmPrimitive;
29import org.openstreetmap.josm.data.osm.Relation;
30import org.openstreetmap.josm.data.osm.RelationMember;
31import org.openstreetmap.josm.data.osm.Way;
32import org.openstreetmap.josm.data.projection.Projection;
33import org.openstreetmap.josm.data.projection.Projections;
34import org.openstreetmap.josm.gui.progress.NullProgressMonitor;
35import org.openstreetmap.josm.gui.progress.ProgressMonitor;
36import org.openstreetmap.josm.tools.Logging;
37
38/**
39 * Reader that reads GeoJSON files. See <a href="https://tools.ietf.org/html/rfc7946">RFC7946</a> for more information.
40 * @since 15424
41 */
42public class GeoJSONReader extends AbstractReader {
43
44 private static final String CRS = "crs";
45 private static final String NAME = "name";
46 private static final String LINK = "link";
47 private static final String COORDINATES = "coordinates";
48 private static final String FEATURES = "features";
49 private static final String PROPERTIES = "properties";
50 private static final String GEOMETRY = "geometry";
51 private static final String TYPE = "type";
52 private JsonParser parser;
53 private Projection projection = Projections.getProjectionByCode("EPSG:4326"); // WGS 84
54
55 GeoJSONReader() {
56 // Restricts visibility
57 }
58
59 private void setParser(final JsonParser parser) {
60 this.parser = parser;
61 }
62
63 private void parse() throws IllegalDataException {
64 while (parser.hasNext()) {
65 Event event = parser.next();
66 if (event == Event.START_OBJECT) {
67 parseRoot(parser.getObject());
68 }
69 }
70 parser.close();
71 }
72
73 private void parseRoot(final JsonObject object) throws IllegalDataException {
74 parseCrs(object.getJsonObject(CRS));
75 switch (object.getString(TYPE)) {
76 case "FeatureCollection":
77 parseFeatureCollection(object.getJsonArray(FEATURES));
78 break;
79 case "Feature":
80 parseFeature(object);
81 break;
82 case "GeometryCollection":
83 parseGeometryCollection(null, object);
84 break;
85 default:
86 parseGeometry(null, object);
87 }
88 }
89
90 /**
91 * Parse CRS as per https://geojson.org/geojson-spec.html#coordinate-reference-system-objects.
92 * CRS are obsolete in RFC7946 but still allowed for interoperability with older applications.
93 * Only named CRS are supported.
94 *
95 * @param crs CRS JSON object
96 * @throws IllegalDataException in case of error
97 */
98 private void parseCrs(final JsonObject crs) throws IllegalDataException {
99 if (crs != null) {
100 // Inspired by https://github.com/JOSM/geojson/commit/f13ceed4645244612a63581c96e20da802779c56
101 JsonObject properties = crs.getJsonObject("properties");
102 if (properties != null) {
103 switch (crs.getString(TYPE)) {
104 case NAME:
105 String crsName = properties.getString(NAME);
106 if ("urn:ogc:def:crs:OGC:1.3:CRS84".equals(crsName)) {
107 // https://osgeo-org.atlassian.net/browse/GEOT-1710
108 crsName = "EPSG:4326";
109 } else if (crsName.startsWith("urn:ogc:def:crs:EPSG:")) {
110 crsName = crsName.replace("urn:ogc:def:crs:", "");
111 }
112 projection = Optional.ofNullable(Projections.getProjectionByCode(crsName))
113 .orElse(Projections.getProjectionByCode("EPSG:4326")); // WGS84
114 break;
115 case LINK: // Not supported (security risk)
116 default:
117 throw new IllegalDataException(crs.toString());
118 }
119 }
120 }
121 }
122
123 private void parseFeatureCollection(final JsonArray features) {
124 for (JsonValue feature : features) {
125 if (feature instanceof JsonObject) {
126 parseFeature((JsonObject) feature);
127 }
128 }
129 }
130
131 private void parseFeature(final JsonObject feature) {
132 JsonValue geometry = feature.get(GEOMETRY);
133 if (geometry != null && geometry.getValueType() == JsonValue.ValueType.OBJECT) {
134 parseGeometry(feature, geometry.asJsonObject());
135 } else {
136 JsonValue properties = feature.get(PROPERTIES);
137 if (properties != null && properties.getValueType() == JsonValue.ValueType.OBJECT) {
138 parseNonGeometryFeature(feature, properties.asJsonObject());
139 } else {
140 Logging.warn(tr("Relation/non-geometry feature without properties found: {0}", feature));
141 }
142 }
143 }
144
145 private void parseNonGeometryFeature(final JsonObject feature, final JsonObject properties) {
146 // get relation type
147 JsonValue type = properties.get(TYPE);
148 if (type == null || properties.getValueType() == JsonValue.ValueType.STRING) {
149 Logging.warn(tr("Relation/non-geometry feature without type found: {0}", feature));
150 return;
151 }
152
153 // create misc. non-geometry feature
154 final Relation relation = new Relation();
155 relation.put(TYPE, type.toString());
156 fillTagsFromFeature(feature, relation);
157 getDataSet().addPrimitive(relation);
158 }
159
160 private void parseGeometryCollection(final JsonObject feature, final JsonObject geometry) {
161 for (JsonValue jsonValue : geometry.getJsonArray("geometries")) {
162 parseGeometry(feature, jsonValue.asJsonObject());
163 }
164 }
165
166 private void parseGeometry(final JsonObject feature, final JsonObject geometry) {
167 if (geometry == null) {
168 parseNullGeometry(feature);
169 return;
170 }
171
172 switch (geometry.getString(TYPE)) {
173 case "Point":
174 parsePoint(feature, geometry.getJsonArray(COORDINATES));
175 break;
176 case "MultiPoint":
177 parseMultiPoint(feature, geometry);
178 break;
179 case "LineString":
180 parseLineString(feature, geometry.getJsonArray(COORDINATES));
181 break;
182 case "MultiLineString":
183 parseMultiLineString(feature, geometry);
184 break;
185 case "Polygon":
186 parsePolygon(feature, geometry.getJsonArray(COORDINATES));
187 break;
188 case "MultiPolygon":
189 parseMultiPolygon(feature, geometry);
190 break;
191 case "GeometryCollection":
192 parseGeometryCollection(feature, geometry);
193 break;
194 default:
195 parseUnknown(geometry);
196 }
197 }
198
199 private LatLon getLatLon(final JsonArray coordinates) {
200 return projection.eastNorth2latlon(new EastNorth(
201 parseCoordinate(coordinates.get(0)),
202 parseCoordinate(coordinates.get(1))));
203 }
204
205 private static double parseCoordinate(JsonValue coordinate) {
206 if (coordinate instanceof JsonString) {
207 return Double.parseDouble(((JsonString) coordinate).getString());
208 } else if (coordinate instanceof JsonNumber) {
209 return ((JsonNumber) coordinate).doubleValue();
210 } else {
211 throw new IllegalArgumentException(Objects.toString(coordinate));
212 }
213 }
214
215 private void parsePoint(final JsonObject feature, final JsonArray coordinates) {
216 fillTagsFromFeature(feature, createNode(getLatLon(coordinates)));
217 }
218
219 private void parseMultiPoint(final JsonObject feature, final JsonObject geometry) {
220 for (JsonValue coordinate : geometry.getJsonArray(COORDINATES)) {
221 parsePoint(feature, coordinate.asJsonArray());
222 }
223 }
224
225 private void parseLineString(final JsonObject feature, final JsonArray coordinates) {
226 if (!coordinates.isEmpty()) {
227 createWay(coordinates, false)
228 .ifPresent(way -> fillTagsFromFeature(feature, way));
229 }
230 }
231
232 private void parseMultiLineString(final JsonObject feature, final JsonObject geometry) {
233 for (JsonValue coordinate : geometry.getJsonArray(COORDINATES)) {
234 parseLineString(feature, coordinate.asJsonArray());
235 }
236 }
237
238 private void parsePolygon(final JsonObject feature, final JsonArray coordinates) {
239 final int size = coordinates.size();
240 if (size == 1) {
241 createWay(coordinates.getJsonArray(0), true)
242 .ifPresent(way -> fillTagsFromFeature(feature, way));
243 } else if (size > 1) {
244 // create multipolygon
245 final Relation multipolygon = new Relation();
246 multipolygon.put(TYPE, "multipolygon");
247 createWay(coordinates.getJsonArray(0), true)
248 .ifPresent(way -> multipolygon.addMember(new RelationMember("outer", way)));
249
250 for (JsonValue interiorRing : coordinates.subList(1, size)) {
251 createWay(interiorRing.asJsonArray(), true)
252 .ifPresent(way -> multipolygon.addMember(new RelationMember("inner", way)));
253 }
254
255 fillTagsFromFeature(feature, multipolygon);
256 getDataSet().addPrimitive(multipolygon);
257 }
258 }
259
260 private void parseMultiPolygon(final JsonObject feature, final JsonObject geometry) {
261 for (JsonValue coordinate : geometry.getJsonArray(COORDINATES)) {
262 parsePolygon(feature, coordinate.asJsonArray());
263 }
264 }
265
266 private Node createNode(final LatLon latlon) {
267 final Node node = new Node(latlon);
268 getDataSet().addPrimitive(node);
269 return node;
270 }
271
272 private Optional<Way> createWay(final JsonArray coordinates, final boolean autoClose) {
273 if (coordinates.isEmpty()) {
274 return Optional.empty();
275 }
276
277 final List<LatLon> latlons = coordinates.stream().map(
278 coordinate -> getLatLon(coordinate.asJsonArray())).collect(Collectors.toList());
279
280 final int size = latlons.size();
281 final boolean doAutoclose;
282 if (size > 1) {
283 if (latlons.get(0).equals(latlons.get(size - 1))) {
284 // Remove last coordinate, but later add first node to the end
285 latlons.remove(size - 1);
286 doAutoclose = true;
287 } else {
288 doAutoclose = autoClose;
289 }
290 } else {
291 doAutoclose = false;
292 }
293
294 final Way way = new Way();
295 way.setNodes(latlons.stream().map(Node::new).collect(Collectors.toList()));
296 if (doAutoclose) {
297 way.addNode(way.getNode(0));
298 }
299
300 way.getNodes().stream().distinct().forEach(it -> getDataSet().addPrimitive(it));
301 getDataSet().addPrimitive(way);
302
303 return Optional.of(way);
304 }
305
306 private static void fillTagsFromFeature(final JsonObject feature, final OsmPrimitive primitive) {
307 if (feature != null) {
308 primitive.setKeys(getTags(feature));
309 }
310 }
311
312 private static void parseUnknown(final JsonObject object) {
313 Logging.warn(tr("Unknown json object found {0}", object));
314 }
315
316 private static void parseNullGeometry(JsonObject feature) {
317 Logging.warn(tr("Geometry of feature {0} is null", feature));
318 }
319
320 private static Map<String, String> getTags(final JsonObject feature) {
321 final Map<String, String> tags = new TreeMap<>();
322
323 if (feature.containsKey(PROPERTIES) && !feature.isNull(PROPERTIES)) {
324 JsonValue properties = feature.get(PROPERTIES);
325 if (properties != null && properties.getValueType() == JsonValue.ValueType.OBJECT) {
326 for (Map.Entry<String, JsonValue> stringJsonValueEntry : properties.asJsonObject().entrySet()) {
327 final JsonValue value = stringJsonValueEntry.getValue();
328
329 if (value instanceof JsonString) {
330 tags.put(stringJsonValueEntry.getKey(), ((JsonString) value).getString());
331 } else if (value instanceof JsonObject) {
332 Logging.warn(
333 "The GeoJSON contains an object with property '" + stringJsonValueEntry.getKey()
334 + "' whose value has the unsupported type '" + value.getClass().getSimpleName()
335 + "'. That key-value pair is ignored!"
336 );
337 } else if (value.getValueType() != JsonValue.ValueType.NULL) {
338 tags.put(stringJsonValueEntry.getKey(), value.toString());
339 }
340 }
341 }
342 }
343 return tags;
344 }
345
346 @Override
347 protected DataSet doParseDataSet(InputStream source, ProgressMonitor progressMonitor) throws IllegalDataException {
348 setParser(Json.createParser(source));
349 try {
350 parse();
351 } catch (JsonParsingException e) {
352 throw new IllegalDataException(e);
353 }
354 return getDataSet();
355 }
356
357 /**
358 * Parse the given input source and return the dataset.
359 *
360 * @param source the source input stream. Must not be null.
361 * @param progressMonitor the progress monitor. If null, {@link NullProgressMonitor#INSTANCE} is assumed
362 * @return the dataset with the parsed data
363 * @throws IllegalDataException if an error was found while parsing the data from the source
364 * @throws IllegalArgumentException if source is null
365 */
366 public static DataSet parseDataSet(InputStream source, ProgressMonitor progressMonitor) throws IllegalDataException {
367 return new GeoJSONReader().doParseDataSet(source, progressMonitor);
368 }
369}
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