The NetBeans IDE includes its own layout manager class, called AbsoluteLayout. It provides design-time support for dragging, resizing and setting absolute positions and sizes for components.
You can use this layout manager at design time, but you do not need to use it after you get your UI set up. Once your UI is designed, switch to GridBagLayout and you'll find your UI looks the same, but you get the benefits of GridBagLayout without all of the overhead of hand-coding constraints. Also consider using the null layout instead of the AbsoluteLayout.
If you want to keep AbsoluteLayout in your GUI application, then you must distribute the AbsoluteLayout class with it. This is permitted, but not recommended.
Source: NetBeans User FAQ