Documentation
Layout Constraints Properties
Layout Constraints properties are related to layout managers. Some layout managers (MigLayout, FormLayout, TableLayout, GridBagLayout, ...) use constraints to associate layout information (e.g. grid x/y) to the child components of a container.
The list of constraints properties depends on the layout manager of the parent component.
Select a component in the Design or Structure view to see its constraints properties in the Properties view.
This screenshot shows constraints properties of a component in a MigLayout.