This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
Do you mean you have a method which wants to know which method has invoked it?
I don't think that you are actually supposed to do that; the idea of a supplier class with public methods is that it is available to all objects without prejudice and without knowing whom it is serving. Bit like a bus; anybody can travel as long as they pay for their ticket, without the driver asking their name!