Understanding Interfaces in Java || Lesson 62 || Java Programming || Learning Programming ||
Understanding Interfaces in Java
In this class, We discuss Understanding Interfaces in Java.
The reader should have prior knowledge of abstract classes and methods. Click Here.
Interface:
An interface is a fully abstract class.
The interface contains abstract methods and static constants.
Example:
interface A
{
int p=20;
void m1();
}
Class B implements A
{
public void m1()
{
System.out.println(“m1 method implemented in B”);
}
}
class test
{
public static void main(String args[])
{
B ob = new B();
ob.m1();
}
}
The Java compiler will convert void m1(); to public abstract void m1(); because A is an interface.
Similarly, int p = 20 is converted to public static final int p = 20;
The compiler adds the extra code.
To inherit the interface, we use the keyword “implements”.
Suppose a class implements an interface. Then all the methods should be implemented.
Interfaces can have static methods.
Example:
interface A
{
int p=20;
public static void staticmethod()
{
System.out.println(“static method”);
}
void m1();
}
Class B implements A
{
public void m1()
{
A.staticmethod();
System.out.println(“m1 method implemented in B”);
}
}
class test
{
public static void main(String args[])
{
B ob = new B();
ob.m1();
}
}
Inheritance for interfaces
interface A
{
int p=20;
void m1();
}
interface B extends A
{
void m2();
}
Class C implements B
{
public void m1()
{
System.out.println(“m1 method implemented in B”);
}
public void m2()
{
System.out.println(“m2 method”);
}
}
class test
{
public static void main(String args[])
{
C ob = new C();
ob.m1();
}
}
Yes, inheritance is applied for interfaces.
Link for playlists:
/ @wisdomerscse
Link for our website: https://learningmonkey.in
Follow us on Facebook @ / learningmonkey
Follow us on Instagram @ / learningmonkey1
Follow us on Twitter @ / _learningmonkey
Mail us @ learningmonkey01@gmail.com
On this page of the site you can watch the video online Understanding Interfaces in Java || Lesson 62 || Java Programming || Learning Programming || with a duration of hours minute second in good quality, which was uploaded by the user Wisdomers - Computer Science and Engineering 02 August 2023, share the link with friends and acquaintances, this video has already been watched 195 times on youtube and it was liked by 8 viewers. Enjoy your viewing!
