ingo@2063: package de.intevation.flys.artifacts.model;
ingo@2063: 
ingo@2063: import net.sf.ehcache.Cache;
ingo@2063: import net.sf.ehcache.Element;
ingo@2063: 
ingo@2063: import org.apache.log4j.Logger;
ingo@2063: 
ingo@2063: import de.intevation.flys.model.Annotation;
ingo@2063: import de.intevation.flys.model.Position;
ingo@2063: 
ingo@2063: import de.intevation.flys.artifacts.cache.CacheFactory;
ingo@2063: import de.intevation.flys.artifacts.model.AnnotationsFactory;
ingo@2063: 
ingo@2063: 
ingo@2063: public class LocationProvider {
ingo@2063: 
ingo@2063:     public static final String CACHE_KEY = "location-provider";
ingo@2063: 
ingo@2063: 
ingo@2063:     private static final Logger logger =
ingo@2063:         Logger.getLogger(LocationProvider.class);
ingo@2063: 
ingo@2063: 
ingo@2063:     private LocationProvider() {
ingo@2063:     }
ingo@2063: 
ingo@2063: 
ingo@2063:     public static String getLocation(String river, double km) {
ingo@2063:         return getLocation(getLocationHash(river, km), river, km);
ingo@2063:     }
ingo@2063: 
ingo@2063: 
ingo@2063:     public static String getLocation(String hash, String river, double km) {
ingo@2063:         logger.debug("Fetch location for '" + river + "' at '" + km + "'");
ingo@2063: 
ingo@2063:         Cache cache = CacheFactory.getCache(CACHE_KEY);
ingo@2063: 
ingo@2063:         if (cache != null) {
ingo@2063:             return getCachedLocation(cache, hash, river, km);
ingo@2063:         }
ingo@2063:         else {
ingo@2063:             logger.info("No Cache for Locations configured.");
ingo@2063:             return getUncachedLocation(river, km);
ingo@2063:         }
ingo@2063:     }
ingo@2063: 
ingo@2063: 
ingo@2063:     protected static String getCachedLocation(
ingo@2063:         Cache cache,
ingo@2063:         String hash,
ingo@2063:         String river,
ingo@2063:         double km
ingo@2063:     ) {
ingo@2063:         logger.debug("Fetch location from cache.");
ingo@2063: 
ingo@2063:         Element element = cache.get(hash);
ingo@2063: 
ingo@2063:         if (element == null) {
ingo@2063:             logger.debug("Element is not in cache yet.");
ingo@2063: 
ingo@2063:             String location = getUncachedLocation(river, km);
ingo@2063:             element = new Element(hash, location);
ingo@2063:             cache.put(element);
ingo@2063:         }
ingo@2063: 
ingo@2063:         return (String) element.getValue();
ingo@2063:     }
ingo@2063: 
ingo@2063: 
ingo@2063:     protected static String getUncachedLocation(String river, double km) {
ingo@2063:         logger.debug("Fetch location from backend.");
ingo@2063: 
ingo@2063:         Annotation annotation = AnnotationsFactory.getAnnotation(river, km);
ingo@2063: 
ingo@2063:         if (annotation != null) {
ingo@2063:             logger.debug("Found an annotation.");
ingo@2063:             Position pos = annotation.getPosition();
ingo@2063:             return pos.getValue();
ingo@2063:         }
ingo@2063: 
ingo@2063:         return "";
ingo@2063:     }
ingo@2063: 
ingo@2063: 
ingo@2063:     protected static String getLocationHash(String river, double km) {
ingo@2063:         return river + "#" + km;
ingo@2063:     }
ingo@2063: }
ingo@2063: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :