org.geomajas.plugin.wms.server.command.WmsGetFeatureInfoCommand.java Source code

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Here is the source code for org.geomajas.plugin.wms.server.command.WmsGetFeatureInfoCommand.java

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/*
 * This is part of Geomajas, a GIS framework, http://www.geomajas.org/.
 *
 * Copyright 2008-2014 Geosparc nv, http://www.geosparc.com/, Belgium.
 *
 * The program is available in open source according to the GNU Affero
 * General Public License. All contributions in this program are covered
 * by the Geomajas Contributors License Agreement. For full licensing
 * details, see LICENSE.txt in the project root.
 */

package org.geomajas.plugin.wms.server.command;

import org.geomajas.command.Command;
import org.geomajas.layer.feature.Feature;
import org.geomajas.plugin.wms.client.service.WmsService.GetFeatureInfoFormat;
import org.geomajas.plugin.wms.server.command.dto.WmsGetFeatureInfoRequest;
import org.geomajas.plugin.wms.server.command.dto.WmsGetFeatureInfoResponse;
import org.geotools.GML;
import org.geotools.GML.Version;
import org.geotools.feature.FeatureCollection;
import org.geotools.feature.FeatureIterator;
import org.opengis.feature.simple.SimpleFeature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.xml.sax.SAXException;

import javax.xml.parsers.ParserConfigurationException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;

/**
 * Command that executes a WMS GetFeatureInfo request. <p/> This command is not part of the API and shouldn't be used
 * directly.
 *
 * @author Pieter De Graef
 * @author An Buyle
 */
@Component
public class WmsGetFeatureInfoCommand implements Command<WmsGetFeatureInfoRequest, WmsGetFeatureInfoResponse> {

    private final Logger log = LoggerFactory.getLogger(WmsGetFeatureInfoCommand.class);

    private static final String PARAM_FORMAT = "info_format";

    public void execute(WmsGetFeatureInfoRequest request, WmsGetFeatureInfoResponse response) throws Exception {
        URL url = new URL(request.getUrl());
        GML gml;

        GetFeatureInfoFormat format = getFormatFromUrl(request.getUrl());
        switch (format) {
        case GML2:
            gml = new GML(Version.GML2);
            response.setFeatures(getFeaturesFromUrl(url, gml, request.getMaxCoordsPerFeature()));
            break;
        case GML3:
            gml = new GML(Version.GML3);
            response.setFeatures(getFeaturesFromUrl(url, gml, request.getMaxCoordsPerFeature()));
            break;
        default:
            String content = readUrl(url);
            response.setWmsResponse(content);
        }
    }

    public WmsGetFeatureInfoResponse getEmptyCommandResponse() {
        return new WmsGetFeatureInfoResponse();
    }

    private List<Feature> getFeaturesFromUrl(URL url, GML gml, int maxCoordsPerFeature)
            throws IOException, SAXException, ParserConfigurationException {
        List<Feature> dtoFeatures = new ArrayList<Feature>();
        FeatureCollection<?, SimpleFeature> collection = gml.decodeFeatureCollection(url.openStream());
        if (null == collection) {
            return dtoFeatures; // empty list
        }
        FeatureConverter converter = new FeatureConverter();
        FeatureIterator<SimpleFeature> it = collection.features();
        if (it.hasNext()) {
            SimpleFeature feature = it.next();
            try {
                dtoFeatures.add(converter.toDto(feature, maxCoordsPerFeature));
            } catch (Exception e) {
                log.error("Error parsing Feature information: " + e.getMessage());
            }
        }
        while (it.hasNext()) {
            SimpleFeature feature = it.next();
            try {
                dtoFeatures.add(converter.toDto(feature, maxCoordsPerFeature));
            } catch (Exception e) {
                // Do nothing...
            }
        }
        return dtoFeatures;
    }

    private GetFeatureInfoFormat getFormatFromUrl(String url) {
        try {
            int index = url.toLowerCase().indexOf(PARAM_FORMAT) + PARAM_FORMAT.length() + 1;
            String format = url.substring(index);
            index = format.indexOf('&');
            if (index > 0) {
                format = format.substring(0, index);
            }
            for (GetFeatureInfoFormat enumValue : GetFeatureInfoFormat.values()) {
                if (enumValue.toString().equalsIgnoreCase(format)) {
                    return enumValue;
                }
            }
        } catch (Exception e) {
            log.error("WMS GetFeatureInfo - Cannot understand which format to request... "
                    + "We'll take HTML format as a fallback." + e.getMessage());
        }
        return GetFeatureInfoFormat.HTML;
    }

    private String readUrl(URL url) throws Exception {
        URLConnection connection = url.openConnection();
        BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));

        StringBuilder response = new StringBuilder();
        String inputLine;
        while ((inputLine = in.readLine()) != null) {
            response.append(inputLine);
        }
        in.close();

        return response.toString();
    }
}