ingo@301: package de.intevation.flys.artifacts.services;
ingo@301: 
ingo@301: import java.math.BigDecimal;
sascha@644: import java.util.Iterator;
ingo@301: 
ingo@301: import org.apache.log4j.Logger;
ingo@301: 
ingo@301: import org.w3c.dom.Document;
ingo@301: import org.w3c.dom.Element;
ingo@301: 
ingo@301: import de.intevation.artifacts.CallMeta;
ingo@301: 
ingo@301: import de.intevation.artifacts.common.ArtifactNamespaceContext;
ingo@301: import de.intevation.artifacts.common.utils.XMLUtils;
ingo@301: import de.intevation.artifacts.common.utils.XMLUtils.ElementCreator;
ingo@301: 
ingo@301: import de.intevation.artifactdatabase.DefaultService;
ingo@301: 
ingo@316: import de.intevation.flys.backend.SessionHolder;
ingo@301: import de.intevation.flys.model.Annotation;
ingo@301: import de.intevation.flys.model.Attribute;
ingo@301: import de.intevation.flys.model.Position;
ingo@301: import de.intevation.flys.model.Range;
ingo@301: 
ingo@301: import de.intevation.flys.artifacts.model.AnnotationsFactory;
ingo@301: 
sascha@314: import org.hibernate.Session;
ingo@301: 
sascha@644: import de.intevation.flys.artifacts.cache.CacheFactory;
sascha@644: 
sascha@644: import net.sf.ehcache.Cache;
sascha@644: 
ingo@301: /**
ingo@301:  * This service provides information about distances of a specified river.
ingo@301:  *
ingo@301:  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
ingo@301:  */
ingo@301: public class DistanceInfoService extends DefaultService {
ingo@301: 
ingo@301:     /** The logger used in this service.*/
ingo@301:     private static Logger logger = Logger.getLogger(DistanceInfoService.class);
ingo@301: 
sascha@644:     public static final String CACHE_NAME = "service-distanceinfo";
sascha@644: 
sascha@644:     public static final String RIVER_XPATH = "/art:river/text()";
sascha@644: 
ingo@301: 
ingo@301:     /**
ingo@301:      * The default constructor.
ingo@301:      */
ingo@301:     public DistanceInfoService() {
ingo@301:     }
ingo@301: 
ingo@301: 
ingo@301:     public Document process(
ingo@301:         Document data,
ingo@301:         Object   globalContext,
ingo@301:         CallMeta callMeta)
ingo@301:     {
ingo@301:         logger.debug("DistanceInfoService.process");
ingo@301: 
ingo@301:         String river = XMLUtils.xpathString(
sascha@644:             data, RIVER_XPATH, ArtifactNamespaceContext.INSTANCE);
ingo@301: 
sascha@644:         if (river == null || (river = river.trim()).length() == 0) {
ingo@301:             logger.warn("No river specified. Cannot return distance info!");
sascha@644:             return XMLUtils.newDocument();
ingo@301:         }
ingo@301: 
ingo@301:         logger.debug("Search distances for river: " + river);
ingo@301: 
sascha@644:         Cache cache = CacheFactory.getCache(CACHE_NAME);
sascha@644: 
sascha@644:         if (cache == null) {
sascha@644:             logger.debug("no cache configured for distance info");
sascha@644:             return getUncached(river);
sascha@644:         }
sascha@644: 
sascha@644:         net.sf.ehcache.Element element = cache.get(river);
sascha@644: 
sascha@644:         if (element != null) {
sascha@644:             logger.debug("distance info found in cache");
sascha@644:             return (Document)element.getValue();
sascha@644:         }
sascha@644: 
sascha@644:         Document result = getUncached(river);
sascha@644: 
sascha@644:         element = new net.sf.ehcache.Element(river, result);
sascha@644: 
sascha@644:         logger.debug("store distance info found into cache");
sascha@644: 
sascha@644:         cache.put(element);
sascha@644: 
sascha@644:         return result;
sascha@644:     }
sascha@644: 
sascha@644:     protected Document getUncached(String river) {
sascha@644: 
sascha@644:         Document result = XMLUtils.newDocument();
sascha@644: 
ingo@301:         ElementCreator ec = new ElementCreator(
ingo@301:             result,
ingo@301:             ArtifactNamespaceContext.NAMESPACE_URI,
ingo@301:             ArtifactNamespaceContext.NAMESPACE_PREFIX);
ingo@301: 
sascha@314:         Session session = SessionHolder.acquire();
ingo@301: 
sascha@644:         try {
sascha@644:             Iterator<Annotation> iter =
sascha@644:                 AnnotationsFactory.getAnnotationsIterator(river);
ingo@301: 
sascha@314:             Element all = ec.create("distances");
sascha@314: 
sascha@644:             while (iter.hasNext()) {
sascha@644:                 Annotation a = iter.next();
sascha@314:                 Element distance = buildDistanceNode(ec, a);
sascha@644:                 all.appendChild(distance);
ingo@301:             }
sascha@314: 
sascha@314:             result.appendChild(all);
ingo@301:         }
sascha@314:         finally {
sascha@314:             session.close();
sascha@314:             SessionHolder.release();
sascha@314:         }
ingo@301: 
ingo@301:         return result;
ingo@301:     }
ingo@301: 
ingo@301: 
ingo@301:     /**
ingo@301:      * This method build an Element for a distance info.
ingo@301:      *
ingo@301:      * @param ec The ElementCreator.
ingo@301:      * @param anno The Annotation that provides information about the distance.
ingo@301:      *
ingo@301:      * @return an Element that contains information about a distance.
ingo@301:      */
sascha@644:     protected static Element buildDistanceNode(ElementCreator ec, Annotation anno) {
ingo@301:         Position  pos   = anno.getPosition();
ingo@301:         Range     range = anno.getRange();
ingo@301:         Attribute attr  = anno.getAttribute();
ingo@301: 
ingo@301:         BigDecimal a = range.getA();
ingo@301:         BigDecimal b = range.getB();
ingo@301: 
ingo@301:         Element distance = ec.create("distance");
ingo@301:         ec.addAttr(distance, "description", pos.getValue(), true);
ingo@301:         ec.addAttr(distance, "from", a != null ? a.toString() : "", true);
ingo@301:         ec.addAttr(distance, "to", b != null ? b.toString() : "", true);
ingo@301:         ec.addAttr(distance, "riverside", attr.getValue(), true);
ingo@301: 
ingo@301:         return distance;
ingo@301:     }
ingo@301: }
ingo@301: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :