--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/artifacts/model/LocationProvider.java	Fri Sep 28 12:14:47 2012 +0200
@@ -0,0 +1,100 @@
+package de.intevation.flys.artifacts.model;
+
+import net.sf.ehcache.Cache;
+import net.sf.ehcache.Element;
+
+import org.apache.log4j.Logger;
+
+import de.intevation.flys.model.Annotation;
+import de.intevation.flys.model.FastAnnotations;
+
+import de.intevation.flys.artifacts.cache.CacheFactory;
+
+public class LocationProvider {
+
+    private static final Logger log =
+        Logger.getLogger(LocationProvider.class);
+
+
+    public static final String CACHE_KEY = "location-provider";
+
+    public static final String PREFIX = "lp-";
+
+
+    private LocationProvider() {
+    }
+
+    public static String getLocation(String river, double km) {
+
+        FastAnnotations fas = getAnnotations(river, km);
+
+        FastAnnotations.Annotation an = fas.findByKm(km);
+
+        return an != null ? an.getPosition() : null;
+    }
+
+    public static FastAnnotations getAnnotations(String river) {
+        return getAnnotations(river, Double.MAX_VALUE);
+    }
+
+    protected static FastAnnotations getAnnotations(String river, double km) {
+
+        Cache cache = CacheFactory.getCache(CACHE_KEY);
+
+        if (cache == null) {
+            return uncachedAnnotations(river, km);
+        }
+
+        String key = PREFIX + river;
+
+        Element element = cache.get(key);
+
+        if (element != null) {
+            return (FastAnnotations)element.getValue();
+        }
+
+        FastAnnotations fas = uncachedAnnotations(river, Double.MAX_VALUE);
+
+        cache.put(new Element(key, fas));
+
+        return fas;
+    }
+
+    protected static FastAnnotations uncachedAnnotations(
+        String river,
+        double km
+    ) {
+        if (km != Double.MAX_VALUE) {
+            // XXX Fake it by using a standard Annotation.
+
+            Annotation annotation =
+                AnnotationsFactory.getAnnotation(river, km);
+
+            if (annotation != null) {
+                FastAnnotations.Annotation fa =
+                    new FastAnnotations.Annotation(
+                        km, Double.NaN,
+                        annotation.getPosition().getValue(), null, null,
+                        Double.NaN, Double.NaN);
+                return new FastAnnotations(
+                    new FastAnnotations.Annotation [] { fa });
+            }
+
+            return new FastAnnotations(new FastAnnotations.Annotation[0]);
+        }
+
+        long startTime = System.currentTimeMillis();
+
+        FastAnnotations fas = new FastAnnotations(river);
+
+        long stopTime = System.currentTimeMillis();
+
+        if (log.isDebugEnabled()) {
+            log.debug("Loading locations took " +
+                (stopTime-startTime)/1000f + " secs.");
+        }
+
+        return fas;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :