In Unified Modeling Language (UML) sequence diagrams,
you can specify class names and types for lifelines.
You must be in the diagram editor and have a sequence
diagram open.
To specify the class name and type for a lifeline in the C/C++ perspective,
in the C/C++ Projects view, click and drag
a C/C++ class or data type onto a lifeline.
The lifeline head is updated with the C/C++ class or data
type.