Index: DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.StiFileCreator/StiFileCreator.cs
===================================================================
diff -u -r3093 -r3099
--- DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.StiFileCreator/StiFileCreator.cs	(.../StiFileCreator.cs)	(revision 3093)
+++ DamTools/LayerOnSlopeTool/trunk/src/Deltares.LayerOnSlopeTool.StiFileCreator/StiFileCreator.cs	(.../StiFileCreator.cs)	(revision 3099)
@@ -19,18 +19,50 @@
 // Stichting Deltares and remain full property of Stichting Deltares at all times.
 // All rights reserved.
 
+using System;
+using System.IO;
+
 namespace Deltares.LayerOnSlopeTool.StiFileCreator
 {
     /// <summary>Class for creating a *.sti file with DGSMStabDam.dll</summary>
     public class StiFileCreator
     {
-        /// <summary>Createng a new .sti file based on the defined input.</summary>
+        /// <summary>Create a new .sti file based on the defined input.</summary>
         /// <param name="stiFileCreatorInput">The sti file creator input.</param>
         /// <param name="outputFilename">The output filename.</param>
-        public void ProcessFile(StiFileCreatorInput stiFileCreatorInput, string outputFilename)
+        public static void ProcessFile(StiFileCreatorInput stiFileCreatorInput, string outputFilename)
         {
+            ValidateInput(stiFileCreatorInput);
             // TODO process file
-            throw new System.NotImplementedException();
         }
+
+        private static void ValidateInput(StiFileCreatorInput stiFileCreatorInput)
+        {
+            if (stiFileCreatorInput == null)
+            {
+                throw new ArgumentNullException("StiFileCreatorInput");
+            }
+
+            if (String.IsNullOrWhiteSpace(stiFileCreatorInput.InputFilename))
+            {
+                throw new ArgumentException("No input filename specified in StiFileCreatorInput");
+            }
+
+            if (!File.Exists(stiFileCreatorInput.InputFilename))
+            {
+                throw new ArgumentException(String.Format("File '{0}' not found", stiFileCreatorInput.InputFilename));
+            }
+
+            if (stiFileCreatorInput.SurfaceLine == null)
+            {
+                throw new ArgumentException("Invalid surfaceline in StiFileCreatorInput");
+            }
+
+            if (String.IsNullOrWhiteSpace(stiFileCreatorInput.DikeMaterialName))
+            {
+                throw new ArgumentException("No dike material name specified in StiFileCreatorInput");
+            }
+
+        }
     }
 }
\ No newline at end of file