Question

Question 7 0 / 10 points What is a Java Interface and what role can it have in developing Data Structures? Support your answer with an example of such an interface. No text entered - Question 8 (10 points) What is meant by a static data structure? In your opinion, what are the advantages and disadvantages of such structures? Do you feel that the advantages outweigh the disadvantages?

Answer 1

Question 7
A java interface is nothing but a collection of abstract methods. Whenever a class implements an interface, it is inheriting the abstract methods inside that interface. And later on, provide its own definition of that method.
The main reasons why interfaces are used:

• It enables the support of multiple inheritance in Java.
• We can achieve loose coupling using this.
• It is used to achieve abstraction.

Role of interface in data structures:
An interface also acts as an abstract data type which only defines the operations supported by the corresponding data structures, but doesn't tell how the data structure implements the specified operations. In other words, it only provides us the details regarding operations supported by it, the arguments accepted and the kind of values returned by it. A data structure thus, can implement this interface to provide definitions to the abstract methods inside it. Those abstract methods were only declaring the methods but the definitions are now given by the classes, which are implementing them. Thus same interface can have multiple implementations based on the classes that are implementing them.

One of the best examples of this is the List interface which is used in Java to maintain ordered collection of elements.

• ArrayList
• LinkedList
• Stack

These are some of the classes which implement List interface. Each one of them use the abstract methods in their own way as required.