Modify the network application for therapy discussed in this chapter so that it saves information for multiple clients. Each client should have its own doctor object. The program should save the...

Modify the network application for therapy discussed in this chapter so that it saves information for multiple clients. Each client should have its own doctor object. The program should save the doctor object for a client when it disconnects. Each doctor object should be associated with a patient username. When a new patient logs in, a new doctor should be created. But when an existing patient logs in, its doctor object should be read from a file having that patient’s username. Each doctor object should have its own history list of a patient’s inputs for generating replies that refer to earlier conversations.