--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/model/HistoricalDischargeDifferenceFacet.java	Thu Apr 25 15:23:37 2013 +0200
@@ -0,0 +1,63 @@
+package org.dive4elements.river.artifacts.model;
+
+import org.apache.log4j.Logger;
+
+import org.dive4elements.artifacts.Artifact;
+import org.dive4elements.artifacts.CallContext;
+
+import org.dive4elements.river.artifacts.FLYSArtifact;
+import org.dive4elements.river.artifacts.states.DefaultState.ComputeType;
+
+
+/**
+ * Difference of historical discharge curve to ...
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class HistoricalDischargeDifferenceFacet
+extends      HistoricalDischargeFacet
+{
+    private static final Logger logger =
+        Logger.getLogger(HistoricalDischargeDifferenceFacet.class);
+
+
+    public HistoricalDischargeDifferenceFacet(
+        int    index,
+        String name,
+        String desc
+    ) {
+        super(index, name, desc, ComputeType.ADVANCE, null, null);
+    }
+
+
+    public HistoricalDischargeDifferenceFacet(
+        int         index,
+        String      name,
+        String      description,
+        ComputeType type,
+        String      stateID,
+        String      hash
+
+    ) {
+        super(index, name, description, type, hash, stateID);
+    }
+
+
+    @Override
+    public Object getData(Artifact artifact, CallContext context) {
+        if (logger.isDebugEnabled()) {
+            logger.debug("Get data for historical discharge difference curves" +
+                " at index: " + index + " / stateId: " + stateId);
+        }
+
+        FLYSArtifact flys = (FLYSArtifact) artifact;
+
+        CalculationResult res = (CalculationResult)
+            flys.compute(context, hash, stateId, type,  false);
+
+        HistoricalDischargeData data = (HistoricalDischargeData) res.getData();
+        WQTimerange[] wqts = (WQTimerange[]) data.getWQTimeranges();
+
+        return wqts[index];
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf-8 :