Sequence Diagram Destroy Markers

[uggi121]

In the unabridged developer guide presented in AB3, the sequence diagram for the delete command doesn't destroy the instance 'd' of the 'DeleteCommand' class. Upon scrutinizing the code in the LogicManager class, it is evident that 'd' is futile after the command has been executed. This is because the resultant details are contained in a 'CommandResult' object.

Below the sequence diagram associated with the developer guide, there is an annotation that highlights an inherent defect of PlantUML which makes it unable to render object lifelines correctly when the object is pre-maturely destroyed, as in the case of the 'DeleteCommandParser' object.

This prompts me to ask - is the lifeline of the 'DeleteCommand' object inaccurately shown as continuing because of an error with PlantUML, or is it because of a subtler additional usage later on?

[damithc]

This prompts me to ask - is the lifeline of the 'DeleteCommand' object inaccurately shown as continuing because of an error with PlantUML, or is it because of a subtler additional usage later on?

It's due to the shortcoming of PlantUML. It's supposed to stop at the X.

[uggi121]

Thank you for the reply Prof. What about DeleteCommand? There is no x marked in the diagram, but I see no further use for it in the caller's code

[damithc]

The X is optional. In most cases it doesn't add much value to the diagram.

[uggi121]

Thank you Master Damith