"Design patterns," generally, are a way of describing the relationships between classes. It makes little sense to ask what design pattern a single class implements, just as it makes little sense to ask what sound a single hand makes in clapping.
If you explain to us where you got the idea to ask this question, maybe we could help you to figure out the answer.
I think you can have a design pattern in a single class. The most common, though not necessarily good, example would be Singleton; this design pattern is often found in a single class.
I wonder if the "intelligent developer" was thinking of immutability. That is a particular implementation pattern, which solves certain problems, such as thread-safety. String is immutable (unless certain black arts are applied).
Betty Rubble? Well, I would go with Betty... but I'd be thinking of Wilma.
Originally posted by Murali Mohan: Can somebody please suggest some good reading materials on design patterns. Preferably names of some good books having some good examples.
Murali Mohan, please don't hijack someone else's topic to ask your question. We have a forum for general questions about patterns. Have a read through the topics in there, you should get some answers to go on.