abstract Keyword Java

abstract Keyword Java

abstract keyword is used to achieve abstraction in Java. it’s use to create abstract class and method.

• abstract class is to contain abstract methods
•  contain non-abstract methods
• must used abstract keyword

abstract class Employee  
{  
    abstract void work();  
}   

Roles

• An abstract keyword cannot be use with variables and constructors.
• If a class is abstract, it cannot be instantiated.
• If a method is abstract, it doesn’t contain the body.
• We cannot use the abstract keyword with the final.
• We cannot declare abstract methods as private.
• We cannot declare abstract methods as static.

Example code

abstract class Animal
{  
    abstract void cat();  
      
}  
class dog extends Animal
{  
  
    @Override  
    void cat() {  
        System.out.println("cat running");  
      
    }  
      
}  
  
public class AbstractExample1 {  
  
    public static void main(String[] args) {  
  
    dog  obj=new dog();  
    obj.cat();  
    }         
}  

Output

cat running