Write data directly to a file.

src/main/java/eu/simstadt/regionchooser/RegionChooserBrowser.java

 package eu.simstadt.regionchooser;
 
+import java.io.BufferedWriter;
 import java.io.File;
 import java.io.IOException;
+import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.logging.Logger;
@@ -76,16 +78,22 @@ public Void call() throws IOException {
 		/**
 		 * This method is called from Javascript, with a prepared wktPolygon written in local coordinates.
 		 */
-		public void downloadRegionFromCityGMLs(String wktPolygon, String project, String csvCitygmls, String srsName)
+		public int downloadRegionFromCityGMLs(String wktPolygon, String project, String csvCitygmls, String srsName)
 				throws IOException, ParseException, XPathParseException, NavException {
 			// It doesn't seem possible to pass arrays or list from JS to Java. So csvCitygmls contains names separated by ;
 			Path[] paths = Stream.of(csvCitygmls.split(";")).map(s -> citygmlPath(project, s)).toArray(Path[]::new);
 
-			StringBuilder sb = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, srsName, paths);
 
-			File buildingIdsFile = selectSaveFileWithDialog(project,
+			File outputFile = selectSaveFileWithDialog(project,
 					csvCitygmls.replace(";", "_").replace(".gml", ""), "selected_region");
-			RegionChooserUtils.writeStringBuilderToFile(sb, buildingIdsFile.toPath());
+
+			int count;
+
+			try (BufferedWriter gmlWriter = Files.newBufferedWriter(outputFile.toPath())) {
+				count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, srsName, gmlWriter, paths);
+			}
+
+			return count;
 		}
 
 

src/main/java/eu/simstadt/regionchooser/RegionChooserCLI.java

 package eu.simstadt.regionchooser;
 
+import java.io.BufferedWriter;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -101,9 +102,10 @@ public Integer call() throws Exception {
 
 		logInfo("WKT Polygon expressed in local coordinates: " + wktPolygon);
 
-		StringBuilder sb = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, localCRS.toString(), citygmls);
-
-		RegionChooserUtils.writeStringBuilderToFile(sb, outputCityGML);
+		try (BufferedWriter gmlWriter = Files.newBufferedWriter(outputCityGML)) {
+			int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, localCRS.toString(), gmlWriter, citygmls);
+			logInfo("Found buildings : " + count);
+		}
 
 		return 0;
 	}

src/main/java/eu/simstadt/regionchooser/RegionExtractor.java

 package eu.simstadt.regionchooser;
 
 import java.io.IOException;
+import java.io.Writer;
 import java.nio.file.Path;
 import java.util.logging.Logger;
 import java.util.regex.Matcher;
@@ -34,10 +35,12 @@
 	 * 
 	 * @param wktPolygon
 	 * @param srsName
+	 * @param output
 	 * @param citygmlPaths
 	 * 
 	 * 
-	 * @return a StringBuffer, full with the extracted Citygml, including header, buildings and footer.
+	 * @writes the extracted Citygml, including header, buildings and footer to output
+	 * @return counts of found building.
 	 * @throws ParseException
 	 * @throws IOException
 	 * @throws XPathEvalException
@@ -45,15 +48,11 @@
 	 * @throws XPathParseException
 	 * @throws NumberFormatException
 	 */
-	static StringBuilder selectRegionDirectlyFromCityGML(String wktPolygon, String srsName, Path... citygmlPaths)
-			throws ParseException, XPathParseException, NavException, IOException {
-
-		//TODO: Should actually write directly to a bufferedwriter
-		//TODO: Should return the number of found buildings.
+	static int selectRegionDirectlyFromCityGML(String wktPolygon, String srsName, Writer sb,
+			Path... citygmlPaths) throws ParseException, XPathParseException, NavException, IOException {
 
 		int buildingsCount = 0;
 		int foundBuildingsCount = 0;
-		StringBuilder sb = new StringBuilder();
 		Geometry poly = WKT_READER.read(wktPolygon);
 
 		CityGmlIterator citygml = null;
@@ -90,7 +89,7 @@ static StringBuilder selectRegionDirectlyFromCityGML(String wktPolygon, String s
 
 		LOGGER.info("Buildings found in selected region " + foundBuildingsCount);
 		sb.append(citygml.getFooter());
-		return sb;
+		return foundBuildingsCount;
 	}
 
 	/**

src/main/java/eu/simstadt/regionchooser/fast_xml_parser/CityGmlIterator.java

@@ -97,7 +97,7 @@ public String getHeader() throws NavException {
 	 * @return Citygml footer
 	 * @throws NavException
 	 */
-	public Object getFooter() throws IOException, NavException {
+	public String getFooter() throws IOException, NavException {
 		int footerOffset = buildingOffset + buildingLength;
 		int footerLength = (int) (Files.size(citygmlPath) - footerOffset);
 		return navigator.toRawString(footerOffset, footerLength);

src/main/resources/eu/simstadt/regionchooser/website/script/simstadt_openlayers.js

@@ -243,8 +243,9 @@ var regionChooser = (function(){
 			if (proj4.defs(srsName)){
 				console.log("Selected region is written in " + srsName + " coordinate system.");
 				try {
-					fxapp.downloadRegionFromCityGMLs(sketchAsWKT(srsName), project, citygmlNames.join(";"), srsName);
-					dataPanel.prepend("<h2 class='ok'>Done!</h2><br/>\n");
+					var count = fxapp.downloadRegionFromCityGMLs(sketchAsWKT(srsName), project, citygmlNames.join(";"), srsName);
+					//FIXME: count looks wrong. too high.
+					dataPanel.prepend("<h2 class='ok'>Done! (" + count + " buildings found) </h2><br/>\n");
 				} catch (e) {
 					console.warn("ERROR : " + e);
 					dataPanel.prepend("<h2 class='error'>Some problem occured!</h2><br/>\n");

src/test/java/eu/simstadt/regionchooser/RegionChooserTests.java

@@ -94,10 +94,6 @@ void testExtractRegionFromTwoCitygmlsInWGS84() throws IOException {
 		assertEquals(22, countBuildings(outGML));
 	}
 
-	private long countBuildings(Path outGML) throws IOException {
-		return Files.readAllLines(outGML).stream().filter(line -> line.contains("bldg:Building gml:id=")).count();
-	}
-
 	@Test
 	void testExtractRegionWithStandardInput() throws IOException {
 		String wktPolygon = "POLYGON((-73.9959209576448 40.73286384885367, -73.996317924579 40.732359794090684, -73.9947515145143 40.7315061442504, -73.99422580154739 40.73214841515045, -73.9959209576448 40.73286384885367))";
@@ -129,5 +125,9 @@ void testExtractRegionWithMissingInput() throws IOException {
 		assertTrue(err.toString().contains(expectedLog), err.toString() + " should contain " + expectedLog);
 		assertFalse(Files.exists(outGML));
 	}
+
+	private long countBuildings(Path outGML) throws IOException {
+		return Files.readAllLines(outGML).stream().filter(line -> line.contains("bldg:Building gml:id=")).count();
+	}
 }
 

src/test/java/eu/simstadt/regionchooser/RegionExtractorTests.java

@@ -3,6 +3,7 @@
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
+import java.io.StringWriter;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.regex.Matcher;
@@ -35,8 +36,10 @@ void testExtract3BuildingsFromGSK3Model() throws Throwable {
 		//NOTE: Small region around Martinskirche in Grünbühl
 		String wktPolygon = "POLYGON((3515848.896028535 5415823.108586172,3515848.9512289143 5415803.590347393,3515829.0815150724 5415803.338023346,3515830.9784850604 5415793.437034622,3515842.0946056456 5415793.272282251,3515843.3515515197 5415766.204935087,3515864.1064344468 5415766.557899496,3515876.489172751 5415805.433782301,3515876.343844858 5415822.009293416,3515848.896028535 5415823.108586172))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("Gruenbuehl.proj/20140218_Gruenbuehl_LOD2.gml");
-		String churchGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31467", citygmlPath)
-				.toString();
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31467", gmlWriter, citygmlPath);
+		String churchGMLString = gmlWriter.toString();
+		assertEquals(3, count);
 		assertEquals(3, countRegexMatches(churchGMLString, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(churchGMLString.contains("Donaustr"));
 		assertTrue(churchGMLString.contains("DEBW_LOD2_203056"));
@@ -56,9 +59,11 @@ void testExtract3BuildingsFromGSK3Model() throws Throwable {
 	void testExtractBuildingsWithCommentsInBetween() throws Throwable {
 		String wktPolygon = "POLYGON((300259.78663489706 62835.835907766595,300230.33294975647 62792.0482567884,300213.5667431851 62770.83143720031,300183.6592861123 62730.20347659383,300252.9947486632 62676.938468840905,300273.3862256562 62701.767105345614,300257.5250407747 62715.760413539596,300308.2754543957 62805.14198211394,300259.78663489706 62835.835907766595))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("NewYork.proj/ManhattanSmall.gml");
-		String archGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, citygmlPath)
-				.toString();
-		assertEquals(countRegexMatches(archGMLString, CITY_OBJECT_MEMBER_REGEX), 2);
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, gmlWriter, citygmlPath);
+		String archGMLString = gmlWriter.toString();
+		assertEquals(2, count);
+		assertEquals(2, countRegexMatches(archGMLString, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(archGMLString.contains("WASHINGTON SQUARE"));
 		assertTrue(archGMLString.contains("uuid_c0980a6e-05ea-4d09-bc83-efab226945a1"));
 		assertTrue(archGMLString.contains("uuid_0985cebb-922d-4b3e-95e5-15dc6089cd28"));
@@ -70,8 +75,10 @@ void testExtractBuildingsWithCommentsInBetween() throws Throwable {
 	void testExtractBuildingsAndChangeEnvelope() throws Throwable {
 		String wktPolygon = "POLYGON((299761.8123557725 61122.68126771413,299721.46983062755 61058.11626595352,299780.84627343423 61021.99295737501,299823.9079725632 61083.3979344517,299761.8123557725 61122.68126771413))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("NewYork.proj/FamilyCourt_LOD2_with_PLUTO_attributes.gml");
-		String familyCourtBuilding = RegionExtractor
-				.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, citygmlPath).toString();
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, gmlWriter, citygmlPath);
+		String familyCourtBuilding = gmlWriter.toString();
+		assertEquals(1, count);
 		assertEquals(1, countRegexMatches(familyCourtBuilding, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(familyCourtBuilding.contains("Bldg_12210021066"));
 		assertFalse(
@@ -95,8 +102,10 @@ void testExtract0BuildingsWithWrongCoordinates() throws Throwable {
 		//NOTE: Small region, far away from NYC
 		String wktPolygon = "POLYGON((0 0, 0 1, 1 1, 1 0, 0 0))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("NewYork.proj/ManhattanSmall.gml");
-		String emptyGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, citygmlPath)
-				.toString();
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, gmlWriter, citygmlPath);
+		String emptyGMLString = gmlWriter.toString();
+		assertEquals(0, count);
 		assertEquals(0, countRegexMatches(emptyGMLString, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(emptyGMLString.contains(CITY_MODEL_HEADER));
 		assertTrue(emptyGMLString.contains(CITY_MODEL_FOOTER));
@@ -107,8 +116,10 @@ void testExtract0BuildingsFromEmptyGML() throws Throwable {
 		//NOTE: Small region, with too many spaces between coordinates
 		String wktPolygon = "POLYGON((0 0, 0 1, 1 1, 1 0, 0 0))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("NewYork.proj/empty_model.gml");
-		String emptyGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, citygmlPath)
-				.toString();
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, gmlWriter, citygmlPath);
+		String emptyGMLString = gmlWriter.toString();
+		assertEquals(0, count);
 		assertEquals(0, countRegexMatches(emptyGMLString, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(emptyGMLString.contains(CORE_CITY_MODEL_HEADER));
 		assertTrue(emptyGMLString.contains(CORE_CITY_MODEL_FOOTER));
@@ -119,8 +130,10 @@ void testExtract0BuildingsFromWeirdGML() throws Throwable {
 		//NOTE: Small region, with too many spaces between coordinates
 		String wktPolygon = "POLYGON((0 0, 0 1, 1 1, 1 0, 0 0))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("NewYork.proj/broken_nyc_lod2.gml");
-		String emptyGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, citygmlPath)
-				.toString();
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, EPSG_32118, gmlWriter, citygmlPath);
+		String emptyGMLString = gmlWriter.toString();
+		assertEquals(0, count);
 		assertEquals(0, countRegexMatches(emptyGMLString, CITY_OBJECT_MEMBER_REGEX));
 		assertTrue(emptyGMLString.contains(CORE_CITY_MODEL_HEADER));
 		assertTrue(emptyGMLString.contains(CORE_CITY_MODEL_FOOTER));
@@ -130,9 +143,11 @@ void testExtract0BuildingsFromWeirdGML() throws Throwable {
 	void testExtractBuildingsFromCitygmlWithoutZinEnvelope() throws Throwable {
 		String wktPolygon = "POLYGON((3512683.1280912133 5404783.732132129,3512719.1608604863 5404714.627650777,3512831.40076119 5404768.344155442,3512790.239106708 5404838.614891164,3512683.1280912133 5404783.732132129))";
 		Path citygmlPath = TEST_REPOSITORY.resolve("Stuttgart.proj/Stuttgart_LOD0_LOD1_small.gml");
-		String emptyGMLString = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31463", citygmlPath)
-				.toString();
-		assertEquals(2, countRegexMatches(emptyGMLString, "<bldg:Building gml:id"));
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31463", gmlWriter, citygmlPath);
+		String twoBuildings = gmlWriter.toString();
+		assertEquals(2, count);
+		assertEquals(2, countRegexMatches(twoBuildings, "<bldg:Building gml:id"));
 	}
 
 	@Test
@@ -141,9 +156,12 @@ void testExtractBuildingsFrom2Citygmls() throws Throwable {
 
 		Path citygml1 = TEST_REPOSITORY.resolve("Stuttgart.proj/Stuttgart_LOD0_LOD1_small.gml");
 		Path citygml2 = TEST_REPOSITORY.resolve("Stuttgart.proj/Stöckach_überarbeitete GML-NoBuildingPart.gml");
-		String emptyGMLString = RegionExtractor
-				.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31463", citygml1, citygml2).toString();
-		assertEquals(17 + 3, countRegexMatches(emptyGMLString, "<bldg:Building gml:id"));
+		StringWriter gmlWriter = new StringWriter();
+		int count = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, "EPSG:31463", gmlWriter, citygml1,
+				citygml2);
+		String gmlFromTwoGMLs = gmlWriter.toString();
+		assertEquals(17 + 3, count);
+		assertEquals(17 + 3, countRegexMatches(gmlFromTwoGMLs, "<bldg:Building gml:id"));
 	}
 
 

src/test/java/eu/simstadt/regionchooser/RegionExtractorWithDifferentInputTests.java

@@ -2,6 +2,7 @@
 
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import java.io.IOException;
+import java.io.StringWriter;
 import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Arrays;
@@ -28,8 +29,9 @@ void testExtractRegionWithLocalCRS()
 		Path citygmlPath = project.resolve(citygml);
 
 		CoordinateReferenceSystem localCRS = RegionChooserUtils.crsFromCityGMLHeader(citygmlPath);
-		StringBuilder sb = RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, localCRS.getName(), citygmlPath);
-		assertTrue(sb.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
+		StringWriter gmlWriter = new StringWriter();
+		RegionExtractor.selectRegionDirectlyFromCityGML(wktPolygon, localCRS.getName(), gmlWriter, citygmlPath);
+		assertTrue(gmlWriter.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
 				"One weird shaped roof should be inside the region");
 	}
 
@@ -44,9 +46,9 @@ void testExtractRegionWithWGS84()
 
 		CoordinateReferenceSystem localCRS = RegionChooserUtils.crsFromCityGMLHeader(citygmlPath);
 		String localWktPolygon = RegionChooserUtils.wktPolygonToLocalCRS(wgs84WktPolygon, localCRS);
-		StringBuilder sb = RegionExtractor.selectRegionDirectlyFromCityGML(localWktPolygon, localCRS.getName(),
-				citygmlPath);
-		assertTrue(sb.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
+		StringWriter gmlWriter = new StringWriter();
+		RegionExtractor.selectRegionDirectlyFromCityGML(localWktPolygon, localCRS.getName(), gmlWriter, citygmlPath);
+		assertTrue(gmlWriter.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
 				"One weird shaped roof should be inside the region");
 	}
 
@@ -90,10 +92,10 @@ void testExtractRegionWithOldCoordinates()
 
 		CoordinateReferenceSystem localCRS = RegionChooserUtils.crsFromCityGMLHeader(citygmlPath);
 		String localWktPolygon = RegionChooserUtils.wktPolygonToLocalCRS(wgs84WktPolygon, localCRS);
-		StringBuilder sb = RegionExtractor.selectRegionDirectlyFromCityGML(localWktPolygon, localCRS.getName(),
-				citygmlPath);
+		StringWriter gmlWriter = new StringWriter();
+		RegionExtractor.selectRegionDirectlyFromCityGML(localWktPolygon, localCRS.getName(), gmlWriter, citygmlPath);
 
-		assertTrue(sb.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
+		assertTrue(gmlWriter.toString().contains("gml_ZVHMQQ6BZGRT0O3Q6RGXF12BDOV49QIZ58XB"),
 				"One weird shaped roof should be inside the region");
 	}
 }