Fixed simulated duck typing in App.

chart_inheritance/src/main/java/edu/unl/cse/soft160/chart_inheritance/App.java

@@ -46,16 +46,19 @@ public class App extends JFrame {
 		context.setFont(TEXT_FONT);
 		context.setColor(TEXT_COLOR);
 		context.setColor(Color.BLUE);
+		for (Class<?> type = chart.getClass(); type != null; type = type.getSuperclass()) {
 			try {
-			chart.getClass().getDeclaredMethod("draw", Graphics2D.class).invoke(chart, context);
+				type.getDeclaredMethod("draw", Graphics2D.class).invoke(chart, context);
+				break;
 			} catch (NoSuchMethodException exception) {
-			throw new RuntimeException(exception);
+				continue;
 			} catch (InvocationTargetException exception) {
 				throw new RuntimeException(exception);
 			} catch (IllegalAccessException exception) {
 				throw new RuntimeException(exception);
 			}
 		}
+	}
 
 	public static void main(String... arguments) {
 		String[] labels = { "Alpha", "Bravo", "Charlie", "Delta", "Echo", "Foxtrot", "Golf" };