--- a/flys-backend/src/main/java/de/intevation/flys/importer/ImportRange.java	Thu Mar 17 16:12:39 2011 +0000
+++ b/flys-backend/src/main/java/de/intevation/flys/importer/ImportRange.java	Thu Mar 17 17:43:57 2011 +0000
@@ -1,6 +1,7 @@
 package de.intevation.flys.importer;
 
 public class ImportRange
+implements   Comparable<ImportRange>
 {
     public Double from;
     public Double to;
@@ -9,6 +10,27 @@
     }
 
     public ImportRange(Double from, Double to) {
+        this.from = from;
+        this.to   = to;
+    }
+
+    private static final int compare(Double a, Double b) {
+        if (a == null && b == null) {
+            return 0;
+        }
+        if (a == null && b != null) {
+            return -1;
+        }
+        if (a != null && b == null) {
+            return +1;
+        }
+        return a.compareTo(b);
+    }
+
+    public int compareTo(ImportRange other) {
+        int cmp = compare(from, other.from);
+        if (cmp != 0) return cmp;
+        return compare(to, other.to);
     }
 
     public Double getFrom() {