Interface in java -topperworld

Interface in java

In Java, an interface is a reference type that defines a set of abstract methods and constants. An interface is similar to a class, but it does not provide an implementation for its methods. Instead, it specifies the signatures of the methods that implementing classes must define. In this blog post, we will delve into the basics of interfaces in Java.

In the below PDF we discuss about Interface in java in detail in simple language, Hope this will help in better understanding.

Declaring Interface :

In Java, an interface is declared using the keyword ‘interface’ followed by the name of the interface. The syntax for declaring an interface is as follows:

interface InterfaceName {
// constant declarations
// method signatures
}

Here, the interface body is enclosed in curly braces and contains constant declarations and method signatures.

In the above PDF Interface is discussed in detail in simple language.

Related Question

What is Interface in java ?

This is a basic question that interviewers may ask to assess your understanding of the concept of interfaces in Java. You can explain that an interface is a reference type that defines a set of abstract methods and constants, but does not provide an implementation for its methods. You can also mention that a class can implement one or more interfaces by providing an implementation for all the methods defined in the interface.

How is an interface different from a class in Java ?

An interface in Java does not provide an implementation for its methods, while a class can provide implementations for its methods.

Can an interface have constants in Java ?

Yes, an interface in Java can have constants, but they cannot be modified by implementing classes.

Can an interface extend another interface in Java ?

Yes, an interface in Java can extend another interface using the ‘extends’ keyword.

What is the significance of the default method in an interface in Java 8 ?

The default method in an interface in Java 8 is a method that provides a default implementation, which can be overridden by implementing classes. This allows interfaces to evolve over time without breaking existing code that implements the interface.