University of Central Florida (UCF) COP3330 Object Oriented Programming Final Practice Exam

In Java, interfaces serve as a mechanism to support multiple inheritance of type, which is why the option about allowing classes to implement multiple contracts is the correct answer. An interface defines a contract that a class can promise to fulfill by implementing the methods declared within the interface. Since a class can implement multiple interfaces, this allows for a form of multiple inheritance where a class can inherit behavior from several sources.

This feature is particularly useful because it enables a class to adopt behaviors from multiple interfaces without being constrained by the limitations of single class inheritance. For instance, a class can implement both `Runnable` and `Serializable` interfaces, thereby inheriting the responsibilities associated with both.

The other options do not effectively describe how interfaces enable multiple inheritance in Java. Providing a default implementation for methods relates to the use of default methods in interfaces, which adds functionality but does not directly establish the principle of multiple inheritance. Defining shared state among classes contradicts the purpose of interfaces, as interfaces do not manage state but rather define behaviors. Lastly, the idea of restricting class inheritance to a single parent actually pertains to class inheritance in Java and does not support the concept of multiple inheritance at all.