Java tutorial
/* * Ktunaxa Referral Management System. * * Copyright (C) see version control system * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package org.ktunaxa.referral.server.mvc; import java.io.BufferedOutputStream; import java.io.ByteArrayInputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.net.URL; import java.util.HashSet; import java.util.zip.ZipEntry; import java.util.zip.ZipInputStream; import org.geomajas.global.GeomajasException; import org.geomajas.service.GeoService; import org.geotools.data.shapefile.ShapefileDataStore; import org.geotools.data.simple.SimpleFeatureIterator; import org.geotools.geometry.jts.JTS; import org.geotools.referencing.CRS; import org.ktunaxa.referral.server.service.KtunaxaConstant; import org.opengis.referencing.crs.CoordinateReferenceSystem; import org.opengis.referencing.operation.MathTransform; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.multipart.MultipartFile; import com.vividsolutions.jts.geom.Geometry; /** * Controller for uploading compressed shape files and sending the union geometry back as WKT. * * @author Pieter De Graef * @author Jan De Moerloose */ @Controller("/upload/referral/geometry/**") public class UploadGeometryController { @Autowired private GeoService geoService; private static final int BUFFER = 2048; private HashSet<String> tempFiles = new HashSet<String>(); private final Logger log = LoggerFactory.getLogger(UploadGeometryController.class); @RequestMapping(value = "/upload/referral/geometry", method = RequestMethod.POST) public String handleFormUpload(@RequestParam(KtunaxaConstant.FORM_ID) String formId, @RequestParam("file") MultipartFile file, Model model) { UploadResponse response = new UploadResponse(); response.addObject(KtunaxaConstant.FORM_ID, formId); try { URL url = unzipShape(file.getBytes()); ShapefileDataStore dataStore = new ShapefileDataStore(url); Geometry geometry = transform(getGeometry(dataStore), dataStore.getFeatureSource().getSchema().getCoordinateReferenceSystem()); response.addObject(KtunaxaConstant.FORM_GEOMETRY, geometry.toText()); } catch (Exception e) { log.error("Could not extract geometry", e); response.setException(e); } cleanup(); model.addAttribute(UploadView.RESPONSE, response); return UploadView.NAME; } private void cleanup() { for (String tempFile : tempFiles) { deleteFileIfExists(tempFile); } tempFiles.clear(); } private Geometry transform(Geometry geometry, CoordinateReferenceSystem crs) throws IOException { try { String sourceCrs = geoService.getCodeFromCrs(crs); // transform to layer CRS first Geometry layerGeom = geoService.transform(geometry, sourceCrs, KtunaxaConstant.LAYER_CRS); return geoService.transform(layerGeom, KtunaxaConstant.LAYER_CRS, KtunaxaConstant.MAP_CRS); } catch (GeomajasException ge) { throw new IOException(ge.getMessage(), ge); } catch (Exception e) { try { CoordinateReferenceSystem targetCrs = geoService.getCrs2(KtunaxaConstant.LAYER_CRS); MathTransform transform = CRS.findMathTransform(crs, targetCrs, true); // have to use JTS transform when EPSG code is missing ! Geometry layerGeom = JTS.transform(geometry, transform); return geoService.transform(layerGeom, KtunaxaConstant.LAYER_CRS, KtunaxaConstant.MAP_CRS); } catch (Exception e1) { throw new IOException(e1.getMessage()); } } } private Geometry getGeometry(ShapefileDataStore dataStore) throws IOException { SimpleFeatureIterator featureIterator = dataStore.getFeatureSource().getFeatures().features(); Geometry geometry = null; while (featureIterator.hasNext()) { if (geometry == null) { geometry = (Geometry) featureIterator.next().getDefaultGeometry(); } else { geometry = geometry.union((Geometry) featureIterator.next().getDefaultGeometry()); } } return geometry; } private URL unzipShape(byte[] fileContent) throws IOException { String tempDir = System.getProperty("java.io.tmpdir"); URL url = null; ZipInputStream zin = new ZipInputStream(new ByteArrayInputStream(fileContent)); try { ZipEntry entry; while ((entry = zin.getNextEntry()) != null) { log.info("Extracting: " + entry); String name = tempDir + "/" + entry.getName(); tempFiles.add(name); if (name.endsWith(".shp")) { url = new URL("file://" + name); } int count; byte[] data = new byte[BUFFER]; // write the files to the disk deleteFileIfExists(name); FileOutputStream fos = new FileOutputStream(name); BufferedOutputStream destination = new BufferedOutputStream(fos, BUFFER); try { while ((count = zin.read(data, 0, BUFFER)) != -1) { destination.write(data, 0, count); } destination.flush(); } finally { destination.close(); } } } finally { zin.close(); } if (url == null) { throw new IllegalArgumentException("Missing .shp file"); } return url; } private void deleteFileIfExists(String name) { File file = new File(name); if (file.exists()) { file.delete(); } } }