The size and positioning of the components can take place in properties the dialogue via selection of the component and following changing of frame position and frame size or by editing the property Bounds in the Properties dialog.
The size of SBeans can be indicated in different ways by the properties MaximumSize, MinimumSize oder PreferredSize. How the different properties affect the resulting position and size, depends on the selected Layout of the container and the Constraintssettings of the component.