diff --git a/src/java/org/apache/poi/sl/draw/DrawShape.java b/src/java/org/apache/poi/sl/draw/DrawShape.java
index ff226be90..1d0eca000 100644
--- a/src/java/org/apache/poi/sl/draw/DrawShape.java
+++ b/src/java/org/apache/poi/sl/draw/DrawShape.java
@@ -135,6 +135,8 @@ public class DrawShape implements Drawable {
                     graphics.translate(-centerX, -centerY);
                 }
                 break;
+            default:
+                throw new RuntimeException("unexpected transform code " + ch);
             }
         }
     }