teichmann@5835: package org.dive4elements.river.client.server;
raimund@1600: 
raimund@1600: import java.util.ArrayList;
raimund@1600: import java.util.List;
raimund@1600: 
raimund@1600: import org.w3c.dom.Document;
raimund@1600: import org.w3c.dom.Element;
raimund@1600: import org.w3c.dom.NodeList;
raimund@1600: 
raimund@1600: import org.apache.log4j.Logger;
raimund@1600: 
raimund@1600: import com.google.gwt.user.server.rpc.RemoteServiceServlet;
raimund@1600: 
teichmann@5835: import org.dive4elements.artifacts.common.ArtifactNamespaceContext;
teichmann@5835: import org.dive4elements.artifacts.common.utils.XMLUtils;
raimund@1600: 
teichmann@5835: import org.dive4elements.artifacts.httpclient.exceptions.ConnectionException;
teichmann@5835: import org.dive4elements.artifacts.httpclient.http.HttpClient;
teichmann@5835: import org.dive4elements.artifacts.httpclient.http.HttpClientImpl;
raimund@1600: 
teichmann@5835: import org.dive4elements.river.client.shared.exceptions.ServerException;
teichmann@5835: import org.dive4elements.river.client.client.services.DischargeInfoService;
teichmann@5835: import org.dive4elements.river.client.shared.model.DischargeInfoObject;
teichmann@5835: import org.dive4elements.river.client.shared.model.DischargeInfoObjectImpl;
raimund@1600: 
raimund@1600: 
raimund@1600: /**
raimund@1600:  * @author <a href="mailto:raimund.renkert@intevation.de">Raimund Renkert</a>
raimund@1600:  */
raimund@1600: public class DischargeInfoServiceImpl
raimund@1600: extends      RemoteServiceServlet
raimund@1600: implements   DischargeInfoService
raimund@1600: {
raimund@1600:     private static final Logger logger =
raimund@1600:         Logger.getLogger(DischargeInfoServiceImpl.class);
raimund@1600: 
raimund@1600:     public static final String ERROR_NO_DISCHARGEINFO_FOUND =
raimund@1600:         "error_no_dischargeinfo_found";
raimund@1600: 
raimund@1600:     public static final String XPATH_DISTANCES = "art:discharges/art:discharge";
raimund@1600: 
raimund@1600: 
raimund@1600:     public DischargeInfoObject[] getDischargeInfo(
raimund@1600:         String locale,
raimund@1600:         long gauge)
raimund@1600:     throws ServerException
raimund@1600:     {
raimund@1600:         logger.info("DichargeInfoServiceImpl.getDischargeInfo");
raimund@1600: 
raimund@1600:         String url  = getServletContext().getInitParameter("server-url");
raimund@1600: 
raimund@1600:         Document doc = XMLUtils.newDocument();
raimund@1600: 
raimund@1600:         XMLUtils.ElementCreator ec = new XMLUtils.ElementCreator(
raimund@1600:             doc,
raimund@1600:             ArtifactNamespaceContext.NAMESPACE_URI,
raimund@1600:             ArtifactNamespaceContext.NAMESPACE_PREFIX);
raimund@1600: 
raimund@1600:         Element gaugeEl = ec.create("gauge");
raimund@1600:         gaugeEl.setTextContent(String.valueOf(gauge));
raimund@1600: 
raimund@1600:         doc.appendChild(gaugeEl);
raimund@1600: 
raimund@1600:         HttpClient client = new HttpClientImpl(url, locale);
raimund@1600: 
raimund@1600:         try {
raimund@1600:             Document result = client.callService(url, "dischargeinfo", doc);
raimund@1600: 
raimund@1600:             logger.debug("Extract discharge info objects now.");
raimund@1600:             DischargeInfoObject[] objects = extractDischargeInfoObjects(result);
raimund@1600: 
raimund@1600:             if (objects != null && objects.length > 0) {
raimund@1600:                 return objects;
raimund@1600:             }
raimund@1600:         }
raimund@1600:         catch (ConnectionException ce) {
raimund@1600:             logger.error(ce, ce);
raimund@1600:         }
raimund@1600: 
raimund@1600:         throw new ServerException(ERROR_NO_DISCHARGEINFO_FOUND);
raimund@1600:     }
raimund@1600: 
raimund@1600:     protected DischargeInfoObject[] extractDischargeInfoObjects(
raimund@1600:         Document result
raimund@1600:     )
raimund@1600:     throws ServerException {
raimund@1600:         NodeList list = result.getElementsByTagName("discharge");
raimund@1600: 
raimund@1600:         if (list == null || list.getLength() == 0) {
raimund@1600:             logger.warn("No discharge info found.");
raimund@1600:             throw new ServerException(ERROR_NO_DISCHARGEINFO_FOUND);
raimund@1600:         }
raimund@1600: 
raimund@1600:         int num = list.getLength();
raimund@1600:         logger.debug("Response contains " + num + " objects.");
raimund@1600: 
raimund@1600:         List<DischargeInfoObject> objects =
raimund@1600:             new ArrayList<DischargeInfoObject>(num);
raimund@1600: 
raimund@1600:         for (int i = 0; i < num; i++) {
raimund@1600:             DischargeInfoObject obj = buildDischargeInfoObject(
raimund@1600:                 (Element)list.item(i));
raimund@1600: 
raimund@1600:             if (obj != null) {
raimund@1600:                 objects.add(obj);
raimund@1600:             }
raimund@1600:         }
raimund@1600: 
raimund@1600:         logger.debug("Retrieved " + objects.size() + " discharges.");
raimund@1600: 
raimund@1600:         return (DischargeInfoObject[])
raimund@1600:             objects.toArray(new DischargeInfoObject[num]);
raimund@1600: 
raimund@1600:     }
raimund@1600: 
raimund@1600:     protected DischargeInfoObject buildDischargeInfoObject(Element node) {
raimund@1600: 
raimund@1600:         String desc      = node.getAttribute("description").trim();
raimund@1600:         String start     = node.getAttribute("start").trim();
raimund@1600:         String end       = node.getAttribute("end").trim();
raimund@1600: 
raimund@1600:         if (start.length() > 0 && end.length() > 0) {
raimund@1600:             try {
raimund@1600:                 Integer startYear  = new Integer(start);
raimund@1600:                 Integer endYear    = new Integer(end);
raimund@1600:                 return new DischargeInfoObjectImpl(desc, startYear, endYear);
raimund@1600:             }
raimund@1600:             catch (NumberFormatException nfe) {
raimund@1600:                 logger.warn(nfe.getLocalizedMessage());
raimund@1600:             }
raimund@1600:         }
raimund@1600: 
raimund@1600:         logger.warn("Invalid distance info object found.");
raimund@1600: 
raimund@1600:         return null;
raimund@1600:     }
raimund@1600: }
raimund@1600: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :