[Enhancement] change to enum or Action Class as aggregation

[1chooo]

In the program, we need to avoid using variables as strings because we might change the names of these variables in the future. Renaming them everywhere would be time-consuming. Instead, we should use enums or an Action class for aggregation.

uml-editor/src/Modes/CreateShapeMode.java

Lines 15 to 32 in dde546a

	public void mousePressed(MouseEvent e) {
	System.out.println("x: " + e.getX() + " y: " + e.getY());
	Shape obj = null;
	switch (shapeType) {
	case "Class":
	obj = new ClassObj(e.getX(), e.getY(), "Class");
	break;
	case "Use Case":
	obj = new UseCaseObj(e.getX(), e.getY(), "Use Case");
	break;
	default:
	System.out.println("Unsupported shape type");
	break;
	}
	if (obj != null) {
	canvas.addShape(obj);
	}
	}

uml-editor/src/Modes/CreateLineMode.java

Lines 26 to 41 in dde546a

	public Line createLine(String type, Point start, Point end) {
	Line line = null;
	switch (type) {
	case "AssociationLine":
	line = new AssociationLine(start.x, start.y, end.x, end.y);
	break;
	case "GeneralizationLine":
	line = new GeneralizationLine(start.x, start.y, end.x, end.y);
	break;
	case "CompositionLine":
	line = new CompositionLine(start.x, start.y, end.x, end.y);
	break;
	}
	return line;
	}