Java Tutorial - Abstract & Interfaces with Example

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Today we are going to learn couple of java OOP ( Object Oriented Programming ) concepts.
Before starting, go through this article: JAVA Tutorial : Inheritance Example Codes

Abstract Class and Example in JAVA:

package interfacez;

/*
 
 This is a simple abstract class. An abstract class is a call of which no object 
 can be created. Use 'abstract' keyword to make a class abstract. 
 Methods can be abstract too. If in a class a method is abstract the class must have
 to be abstract.
 */
public abstract class myabstractclass {

	public static void main(String[] args) {
		// TODO Auto-generated method stub

	}
	
	/*
	 An abstract method must not have a body. 
	 In an abstract class you can have a non abstract method.
	 */
	abstract public void specialAbstractMethod();

}

Java interface: Creating Java Interface

package interfacez;
/* This is my interface. I will inherit this from my main class.
  This is also the java super class for my main class from which i will
  call this file and access those methods.



*/
public interface createinterface {

	// creating four methods
	public void website();
	public void android_app();
	public void ios_app();
	public void windows_app();
}

Java interface: Calling methods from main class

package interfacez;

/*
 Interface is a type that brings behaviors which a class can implement according to its need.
 implements keyword is used to implement an interface in a java class.
 Interface is a class like thing which is 100% abstract. A class can implement 
 any number of interfaces that it wants.If needed interface can be extended using
 inheritance concept of OOP( Object Oriented Programming. )
 
 
 */
public class myinterfaceclass implements createinterface{

	public static void main(String[] args) {
		/* creating object for my class, so that i can call the methods that have
		come from interface.
	*/
		myinterfaceclass Apps_Object = new myinterfaceclass();
		
		/*
		 Calling the methods using my object.
		 
		 */
		Apps_Object.website();
		Apps_Object.ios_app();
		Apps_Object.android_app();
		Apps_Object.windows_app();
		
	}
	
	/*
	 Overriding the abstract methods that have come from interface.
	 
	 */ 
	
	public void website(){
		System.out.println("Java tutorials on my website.");
	}
	public void android_app(){
		System.out.println("PHP tutorials on my android app.");		
	}
	public void ios_app(){
		System.out.println("JavaScript tutorials on my iOS App.");
	}
	public void windows_app(){
		System.out.println("C Sharp ( C# ) on my windows app.");
	}

	
}

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