Used in a sequence diagram, an object lifeline represents the existence of an object at a particular time. If the object is created or destroyed during the time period the diagram represents, then the lifeline stops or starts at the appropriate point. An object's destruction is marked with a large X.
Name an Object Lifeline shape and add other property values
Double-click the shape and then type the name you want in the UML <element> Properties dialog box.
Control which property values are displayed on the Object Lifeline shape
Right-click the shape, click Shape Display Options, and then select or clear options to show or hide values.
Display a destruction marker
Right-click the Object Lifeline shape, click Shape Display Options, and then select Destruction marker.