@Override
	public Dimension preferredLayoutSize(Container container) {
		Component[] components = container.getComponents();
        if ( components.length == 0 ) {
            return new Dimension(0, 0);
        }
        
        Component component = components[0];
        if ( component == null ) {
            return new Dimension(0, 0); // shouldn't happen
        }
		
		Dimension size = new Dimension(component.getPreferredSize());
		Insets insets = container.getInsets();
		size.height += insets.top + insets.bottom;
		size.width += insets.left + insets.right;		
		return size;
	}
Puts the first child of the given component in the middle of the component, both vertically
and horizontally.
Ghidra/Framework/Gui/src/main/java/ghidra/util/layout/MiddleLayout.java