--- a/artifacts/src/main/java/org/dive4elements/river/artifacts/WINFOArtifact.java	Wed Jun 06 14:15:58 2018 +0200
+++ b/artifacts/src/main/java/org/dive4elements/river/artifacts/WINFOArtifact.java	Wed Jun 06 14:16:28 2018 +0200
@@ -20,6 +20,7 @@
 
 import org.dive4elements.river.artifacts.access.Calculation4Access;
 import org.dive4elements.river.artifacts.access.RangeAccess;
+import org.dive4elements.river.artifacts.access.RiverAccess;
 import org.dive4elements.river.artifacts.access.ComputationRangeAccess;
 import org.dive4elements.river.artifacts.geom.Lines;
 
@@ -42,8 +43,6 @@
 
 import org.dive4elements.river.artifacts.states.DefaultState.ComputeType;
 
-import org.dive4elements.river.artifacts.states.LocationDistanceSelect;
-
 import org.dive4elements.river.model.DischargeTable;
 import org.dive4elements.river.model.FastCrossSectionLine;
 import org.dive4elements.river.model.Gauge;
@@ -174,7 +173,7 @@
         return this.getWaterlevelData(null);
     }
 
-    protected CalculationResult getDischargeLongitudinalSectionData() {
+    private CalculationResult getDischargeLongitudinalSectionData() {
         // TODO: This caluclation should be cached as it is quite expensive.
         return new Calculation4(new Calculation4Access(this)).calculate();
     }
@@ -191,44 +190,51 @@
         String calculationMode = getDataAsString("calculation_mode");
 
         // If this WINFO-Artifact has a calculation trait.
-        if (calculationMode != null) {
-            if (calculationMode.equals("calc.discharge.longitudinal.section")
-            ) {
+        if (calculationMode != null) 
+        {
+            if (calculationMode.equals("calc.discharge.longitudinal.section"))
                 return getDischargeLongitudinalSectionData();
-            }
-            else if (calculationMode.equals("calc.extreme.curve")) {
-                return (CalculationResult)
-                    this.compute(context, ComputeType.ADVANCE, false);
-            }
-            else if (calculationMode.equals("calc.w.differences")) {
-                return (CalculationResult)
-                    this.compute(context, ComputeType.ADVANCE, true);
-            }
-            else {
-                log.warn("Unhandled calculation_mode " + calculationMode);
-            }
+
+            if (calculationMode.equals("calc.extreme.curve")) 
+                return (CalculationResult)this.compute(context, ComputeType.ADVANCE, false);
+
+            if (calculationMode.equals("calc.w.differences")) 
+                return (CalculationResult)this.compute(context, ComputeType.ADVANCE, true);
+            
+            log.warn("Unhandled calculation_mode " + calculationMode);
         }
-
+        
         // Otherwise get it from parameterization.
-        River river = RiverUtils.getRiver(this);
-        if (river == null) {
+        // TODO: wrong comment: now always a waterlevle computation is executed; actually there is a calc_mode for that, why dont check?
+        return computeWaterlevelData();
+    }
+
+    /** Execu5tes the calculation of 'waterlevel', fetches all input data from this artifact */
+    private CalculationResult computeWaterlevelData() {
+        final double[] kms = new ComputationRangeAccess(this).getKms();
+        if (kms == null) 
+            return error(new WQKms[0], "no.kms.selected");
+
+        return computeWaterlevelData(kms);
+    }
+    
+    /** 
+     * Execu5tes the calculation of 'waterlevel'.
+     * Allows to override the stations for which the calculation is done. All other inputs are fetched from this artifact.
+     */
+    public final CalculationResult computeWaterlevelData(final double kms[]) {
+
+        final River river = new RiverAccess(this).getRiver();
+        if (river == null) 
             return error(new WQKms[0], "no.river.selected");
-        }
-
-        double[] kms = getKms();
-        if (kms == null) {
-            return error(new WQKms[0], "no.kms.selected");
-        }
 
         double[] qs   = getQs();
         double[] ws   = null;
-        boolean  qSel = true;
 
         Calculation report = new Calculation();
 
         if (qs == null) {
             log.debug("Determine Q values based on a set of W values.");
-            qSel = false;
             ws   = getWs();
             double [][] qws = getQsForWs(ws, report);
             if (qws == null || qws.length == 0) {
@@ -273,10 +279,9 @@
                 "reference gauge: " + gauge.getName() + " (km " + refKm + ")");
         }
 
-        return computeWaterlevelData(kms, qs, ws, wst, refKm, report);
+        return computeWaterlevelData(kms, qs, ws, wst, refKm, report);        
     }
 
-
     /**
      * Computes the data of a waterlevel computation based on the interpolation
      * in WstValueTable.
@@ -287,7 +292,7 @@
      *
      * @return an array of data triples that consist of W, Q and Kms.
      */
-    public static CalculationResult computeWaterlevelData(
+    private static CalculationResult computeWaterlevelData(
         double []     kms,
         double []     qs,
         double []     ws,
@@ -349,7 +354,7 @@
      *
      * @return the computed data.
      */
-    public static CalculationResult computeDurationCurveData(
+    private static CalculationResult computeDurationCurveData(
         Gauge         gauge,
         WstValueTable wst,
         double        location)
@@ -409,7 +414,7 @@
      * @return an object that contains tuples of W/Q values at the specified
      * location.
      */
-    public static CalculationResult computeDischargeCurveData(
+    private static CalculationResult computeDischargeCurveData(
         WstValueTable wst,
         double location)
     {
@@ -544,7 +549,7 @@
     /**
      * Get corrected waterline against surface/profile.
      */
-    public Lines.LineData waterLineC(int idx, FastCrossSectionLine csl) {
+    private Lines.LineData waterLineC(int idx, FastCrossSectionLine csl) {
         List<Point2D> points = csl.getPoints();
 
         WQKms[] wqckms = (WQKms[])
@@ -665,7 +670,7 @@
      *
      * @return an array of Q values.
      */
-    public double [][] getQsForWs(double[] ws, Calculation report) {
+    private double [][] getQsForWs(double[] ws, Calculation report) {
 
         if (ws == null) {
             log.error("getQsForWs: ws == null");
@@ -803,19 +808,6 @@
 
 
     /**
-     * Returns the selected Kms.
-     *
-     * @return the selected kms.
-     */
-    public double[] getKms() {
-        return new ComputationRangeAccess(this).getKms();
-    }
-
-    public double [] getFromToStep() {
-        return new ComputationRangeAccess(this).getFromToStep();
-    }
-
-    /**
      * This method returns the Q values.
      *
      * @return the selected Q values or null, if no Q values are selected.