4 files changed, 10 insertions, 1 deletions
diff --git a/src/newt/classes/com/jogamp/newt/NewtFactory.java b/src/newt/classes/com/jogamp/newt/NewtFactory.java
index 82f74e370..61dbfb34c 100644
--- a/src/newt/classes/com/jogamp/newt/NewtFactory.java
+++ b/src/newt/classes/com/jogamp/newt/NewtFactory.java
@@ -63,8 +63,8 @@ public class NewtFactory {
             try {
                 clazz = Class.forName(clazzName);
             } catch (Throwable t) {
-                System.err.println("Warning: Failed to find class <"+clazzName+">: "+t.getMessage());
                 if(DEBUG_IMPLEMENTATION) {
+                    System.err.println("Warning: Failed to find class <"+clazzName+">: "+t.getMessage());
                     t.printStackTrace();
                 }
             }
diff --git a/src/newt/classes/jogamp/newt/DisplayImpl.java b/src/newt/classes/jogamp/newt/DisplayImpl.java
index f2f35135a..a0bbcc264 100644
--- a/src/newt/classes/jogamp/newt/DisplayImpl.java
+++ b/src/newt/classes/jogamp/newt/DisplayImpl.java
@@ -70,6 +70,9 @@ public abstract class DisplayImpl extends Display {
                 throw new RuntimeException("Unknown display type \"" + type + "\"");
             }
         }
+        if(null==displayClass) {
+            throw new ClassNotFoundException("Failed to find NEWT Display Class <"+type+".Display>");            
+        }
         return displayClass;
     }
 
diff --git a/src/newt/classes/jogamp/newt/ScreenImpl.java b/src/newt/classes/jogamp/newt/ScreenImpl.java
index 72f1b5a2c..cf614b6f1 100644
--- a/src/newt/classes/jogamp/newt/ScreenImpl.java
+++ b/src/newt/classes/jogamp/newt/ScreenImpl.java
@@ -111,6 +111,9 @@ public abstract class ScreenImpl extends Screen implements ScreenModeListener {
                 throw new RuntimeException("Unknown window type \"" + type + "\"");
             }
         }
+        if(null==screenClass) {
+            throw new ClassNotFoundException("Failed to find NEWT Screen Class <"+type+".Screen>");            
+        }
         return (Class<? extends Screen>)screenClass;
     }
 
diff --git a/src/newt/classes/jogamp/newt/WindowImpl.java b/src/newt/classes/jogamp/newt/WindowImpl.java
index 143e7c1ed..074f635e4 100644
--- a/src/newt/classes/jogamp/newt/WindowImpl.java
+++ b/src/newt/classes/jogamp/newt/WindowImpl.java
@@ -170,6 +170,9 @@ public abstract class WindowImpl implements Window, NEWTEventConsumer
                 throw new NativeWindowException("Unknown window type \"" + type + "\"");
             }
         }
+        if(null==windowClass) {
+            throw new ClassNotFoundException("Failed to find NEWT Window Class <"+type+".Window>");            
+        }
         return windowClass;
     }