KmlLinkServlet.java example

Explorer
activityinfo-master
package org.activityinfo.server.endpoint.kml;

/*
 * #%L
 * ActivityInfo Server
 * %%
 * Copyright (C) 2009 - 2013 UNICEF
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public 
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */

import com.google.inject.Inject;
import com.google.inject.Singleton;
import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

/**
 * Serves a simple KML file containing a network link to
 * {@link org.activityinfo.server.endpoint.kml.KmlDataServlet}.
 * <p/>
 * This file will be downloaded to the users computer and can be saved locally,
 * but will asssure that all actual data comes live from the server.
 *
 * @author Alex Bertram (akbertram@gmail.com)
 */
@Singleton
public class KmlLinkServlet extends HttpServlet {

    private final Configuration templateCfg;

    @Inject
    public KmlLinkServlet(Configuration templateCfg) {
        this.templateCfg = templateCfg;
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        Map<String, Object> link = new HashMap<String, Object>();

        link.put("href", "http://" + req.getServerName() + ":" +
                         req.getServerPort() + "/" + req.getRequestURI() + "/activities");

        Template tpl = templateCfg.getTemplate("kml/NetworkLink.kml.ftl");
        resp.setContentType("application/vnd.google-earth.kml+xml;");
        resp.setCharacterEncoding("UTF-8");
        resp.setHeader("Content-Disposition", "attachment; filename=ActivityInfo.kml");

        try {
            tpl.process(link, resp.getWriter());
        } catch (TemplateException e) {
            resp.setStatus(500);
            e.printStackTrace();
        }
    }
}