code: private String getTag(final BorderLayoutConstraint constraint) {
  		switch (constraint) {
  			case EAST:
  				return "ui:east";
  			case NORTH:
  				return "ui:north";
  			case SOUTH:
  				return "ui:south";
  			case WEST:
  				return "ui:west";
  			case CENTER:
  
  			default:
  				return "ui:center";
  		}
  	}
docs: Retrieves the name of the element that will contain components with the given constraint.
  
  @param constraint the constraint to retrieve the tag for.
  @return the tag for the given constraint.