public List<Object[]> getShapes() {
List<Object[]> shapesCollection = new ArrayList<Object[]>();
for (int i = 0; i < shapes.size(); i++) {
shapesCollection.add(shapes.get(i).toObjectArray());
}
return shapesCollection;
}
public void undo() {
if (shapes.size() > 0) shapes.remove(shapes.size() - 1);
}
public void clear() {
shapes.clear();
}
public void addShape(Shape shape) {
shapes.add(shape);
}