minor error message

tools.descartes.pmx/src/tools/descartes/pmx/PMXController.java

@@ -118,11 +118,14 @@ public class PMXController {
 	}
 
 	public static IModelBuilder getModelBuilder() {
+		if (modelBuilder == null) {
+			log.error("builder not initialized");
+		}
 		return modelBuilder;
 	}
 
-	public static void setModelBuilder(IModelBuilder modelBuilder2) {
-		modelBuilder = modelBuilder2;
+	public static void setModelBuilder(IModelBuilder newModelBuilder) {
+		modelBuilder = newModelBuilder;
 	}