Create class diagrams that describe the classes and relationships depicted in the following scenarios:
• Researchers are placed into a database that is maintained by the state of Georgia. Information of interest includes researcher name, title, position, date began current position, number of years at current position; university name, location, enrollment; and research interests. Researchers are associated with one institution, and each researcher can have up to five research interests. More than one researcher can have the same interest, and the system tracks the ranking of the best researchers for each interest. The system should be able to insert new researchers, universities, and research interests; produce information, such as the number of researchers at each university, contact information for the researchers, and research interests that do not have associated researchers; and change researcher rankings for the various research interests.
• A department store has a bridal registry. This registry keeps information about the bride, the products that the store carries, and the products for which each customer registers. Some products include several related items; for example, dish sets include plates, specialty dishes, and serving bowls. Customers typically register for a large number of products, and many customers register for the same products. Draw the class diagram and give at least two examples of query and update operations that could be placed somewhere on the model.
• Jim Smith’s dealership sells Fords, Hondas, and Toyotas. The dealership keeps information about each car manufacturer with whom employees deal so that they can get in touch with manufacturers easily. The dealership also keeps basic information about the models of cars that it carries from each manufacturer. The dealership keeps such information as list price, the price the dealership paid to obtain the model, and the model name and series (e.g., Honda Civic LX). It also keeps information about all sales that employees have made. (For instance, the dealership will record the buyer’s name, the car he or she bought, and the amount the buyer paid for the car.) To contact the buyers in the future, the dealership also keeps contact information (e.g., address, phone number).