--- a/flys-artifacts/ChangeLog	Fri Feb 10 08:41:07 2012 +0000
+++ b/flys-artifacts/ChangeLog	Fri Feb 10 08:43:06 2012 +0000
@@ -1,3 +1,9 @@
+2012-02-09  Ingo Weinzierl <ingo@intevation.de>
+
+	* src/main/java/de/intevation/flys/exports/ChartHelper.java: Added a
+	  helper function to determine the min and max bounds (x and y) for
+	  TimeSeriesCollections.
+
 2012-02-09  Ingo Weinzierl <ingo@intevation.de>
 
 	* src/main/java/de/intevation/flys/jfree/TimeBounds.java,

--- a/flys-artifacts/src/main/java/de/intevation/flys/exports/ChartHelper.java	Fri Feb 10 08:41:07 2012 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/exports/ChartHelper.java	Fri Feb 10 08:43:06 2012 +0000
@@ -2,9 +2,16 @@
 
 import org.jfree.data.Range;
 import org.jfree.data.xy.XYDataset;
+import org.jfree.data.time.RegularTimePeriod;
+import org.jfree.data.time.TimeSeriesCollection;
+import org.jfree.data.time.TimeSeries;
 
 import org.apache.log4j.Logger;
 
+import de.intevation.flys.jfree.Bounds;
+import de.intevation.flys.jfree.DoubleBounds;
+import de.intevation.flys.jfree.TimeBounds;
+
 
 /**
  * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
@@ -73,6 +80,63 @@
     }
 
 
+    public static Bounds[] getBounds(TimeSeriesCollection collection) {
+        int seriesCount = collection != null ? collection.getSeriesCount() : 0;
+
+        if (seriesCount == 0) {
+            logger.warn("TimeSeriesCollection is empty or has no Series set.");
+            return null;
+        }
+
+        boolean foundValue = false;
+
+        long lowerX = Long.MAX_VALUE;
+        long upperX = -Long.MAX_VALUE;
+
+        double lowerY = Double.MAX_VALUE;
+        double upperY = -Double.MAX_VALUE;
+
+        for (int i = 0, m = seriesCount; i < m; i++) {
+            TimeSeries series = collection.getSeries(i);
+
+            for (int j = 0, n = collection.getItemCount(i); j < n; j++) {
+                RegularTimePeriod rtp = series.getTimePeriod(j);
+
+                if (rtp == null) {
+                    continue;
+                }
+
+                foundValue = true;
+
+                long start = rtp.getFirstMillisecond();
+                long end   = rtp.getLastMillisecond();
+
+                if (start < lowerX) {
+                    lowerX = start;
+                }
+
+                if (end > upperX) {
+                    upperX = end;
+                }
+
+                double y = series.getValue(j).doubleValue();
+
+                lowerY = Math.min(lowerY, y);
+                upperY = Math.max(upperY, y);
+            }
+        }
+
+        if (foundValue) {
+            return new Bounds[] {
+                new TimeBounds(lowerX, upperX),
+                new DoubleBounds(lowerY, upperY)
+            };
+        }
+
+        return null;
+    }
+
+
     /**
      * Expand range by percent.
      *