1 files changed, 20 insertions, 3 deletions
diff --git a/src/de/lmu/ifi/dbs/elki/utilities/optionhandling/WrongParameterValueException.java b/src/de/lmu/ifi/dbs/elki/utilities/optionhandling/WrongParameterValueException.java
index eeb6a9e7..3f34efb7 100644
--- a/src/de/lmu/ifi/dbs/elki/utilities/optionhandling/WrongParameterValueException.java
+++ b/src/de/lmu/ifi/dbs/elki/utilities/optionhandling/WrongParameterValueException.java
@@ -4,7 +4,7 @@ package de.lmu.ifi.dbs.elki.utilities.optionhandling;
  This file is part of ELKI:
  Environment for Developing KDD-Applications Supported by Index-Structures
 
- Copyright (C) 2013
+ Copyright (C) 2014
  Ludwig-Maximilians-Universität München
  Lehr- und Forschungseinheit für Datenbanksysteme
  ELKI Development Team
@@ -54,7 +54,7 @@ public class WrongParameterValueException extends ParameterException {
    * @param cause the cause
    */
   public WrongParameterValueException(Parameter<?> parameter, String read, Throwable cause) {
-    this("Wrong value of parameter \"" + parameter.getName() + "\".\n" + "Read: " + read + ".\n" + "Expected: " + parameter.getFullDescription() + "\n" + cause.getMessage(), cause);
+    this("Wrong value of parameter \"" + parameter.getName() + "\".\n" + "Read: " + read + ".\n" + "Expected: " + parameter.getFullDescription() + "\n" + formatCause(cause), cause);
   }
 
   /**
@@ -66,7 +66,7 @@ public class WrongParameterValueException extends ParameterException {
    * @param cause the cause
    */
   public WrongParameterValueException(Parameter<?> parameter, String read, String reason, Throwable cause) {
-    this("Wrong value of parameter " + parameter.getName() + ".\n" + "Read: " + read + ".\n" + "Expected: " + parameter.getFullDescription() + "\n" + reason + "\n" + cause.getMessage(), cause);
+    this("Wrong value of parameter " + parameter.getName() + ".\n" + "Read: " + read + ".\n" + "Expected: " + parameter.getFullDescription() + "\n" + reason + "\n" + formatCause(cause), cause);
   }
 
   /**
@@ -98,4 +98,21 @@ public class WrongParameterValueException extends ParameterException {
   public WrongParameterValueException(String message, Throwable e) {
     super(message, e);
   }
+
+  /**
+   * Format the error cause.
+   * 
+   * @param cause Error cause.
+   * @return String representation
+   */
+  private static String formatCause(Throwable cause) {
+    if(cause == null) {
+      return "";
+    }
+    String message = cause.getMessage();
+    if(message != null) {
+      return message;
+    }
+    return cause.toString();
+  }
 }