Interface

[kamlesh tayade]

What is the difference between Class and Interface. as it class only extended and Interface are implemented.

[Santana Iyer]

class can extend only one class but can implement many interfaces

for e.g.

interface Inter1 { }
interface Inter2 { }
class Super { }
class Sub extends Super implements Inter1, Inter2
{
}


interface can only extends one or more interface.

interface can not implement anything and it can not extends class but can only extend interface.

[A Kumar]

Hi,

Another one you can add...

Interface - No constructor..

Class - have constructors

[ruber arain]

In Addition,
Interaces define only methods and constants. not variables.
Classes implement these.

[A Kumar]

Interaces define [B]only {/B] methods and constants. not variables.

Please have a look at the code below...

 
 

 
public class EnclosingInterface implements BACD{
 
    private static interface inInter {
    int k=10;    
    
    }
 
    private static class inClass implements inInter {}
 
    
 
    public static void main(String[] args) {
 
      inClass in = new inClass();
 
    }
 
  }
 

abstract interface BACD{ 
    int i=10;
    class classinterface{
        
    }
}
 

 

 

 

Regards

[agrah upadhyay]

Interaces define only methods and constants. not variables.

Interfaces may define variables which are implicitly public static and final.

[Lakshmanan Arunachalam]

Interfaces : All methods are public, abstract implicitly, they can't have implementation. All fields are constant i.e static final. They can't be instantiated as like abstract classes.
Classes: Methods can be abstract/concrete. Fields can be constants/variables(class/instance)