11. What type of variable can be defined in an interface?

1. 1. public final

   
   
   

   2. public static

   
   
   

   3. static final

   
   
   

   4. private final

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   variable defined in an interface is implicitly final and static. They are usually written in capital letters.

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12. What does an interface contain?

1. 1. Method declaration

   
   
   

   2. Method name

   
   
   

   3. Method definition

   
   
   

   4. Method declaration and definition

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   Interface contains the only declaration of the method.

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13. What type of methods an interface contain by default?

1. 1. static

   
   
   

   2. final

   
   
   

   3. private

   
   
   

   4. abstract

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   By default, interface contains abstract methods. The abstract methods need to be implemented by concrete classes.

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14. What will happen if we provide concrete implementation of method in interface?

1. 1. Compilation failure

   
   
   

   2. The concrete class implementing that method need not provide implementation of that method

   
   
   

   3. Method not found exception is thrown

   
   
   

   4. Runtime exception is thrown

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   The methods of interfaces are always abstract. They provide only method definition.

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15. What happens when a constructor is defined for an interface?

1. 1. Runtime Exception

   
   
   

   2. The interface compiles successfully

   
   
   

   3. The implementing class will throw exception

   
   
   

   4. Compilation failure

   
   
   

   5. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   Constructor is not provided by interface as objects cannot be instantiated.

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