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1. An abstract class can declare instance data? 2. An abstract class can extend

ID: 3628495 • Letter: 1

Question

1. An abstract class can declare instance data?
2. An abstract class can extend another class?
3. An abstract class can extend a non-abstract class?
4. An interface is an abstract class?
5. An interface can declare instance data?
6. Any method in an interface must be public?
7. All methods in an interface must be abstract?
8. An interface can have no methods at all?
9. An interface can extend another interface?
10. An interface can declare constructors?
11. Object is an abstract class?
12. Methods in an interface may provide a throws list?

Explanation / Answer

1. An abstract class can declare instance data?

No, we can’t instantiate abstract class directly.

     2. An abstract class can extend another class?

Yes.

3. An abstract class can extend a non-abstract class?

Yes.
4. An interface is an abstract class?

      No.
5. An interface can declare instance data?

No.
6. Any method in an interface must be public?

Yes.
7. All methods in an interface must be abstract?

Yes.
8. An interface can have no methods at all?

Yes.
9. An interface can extend another interface?

Yes
10. An interface can declare constructors?

No.
11. Object is an abstract class?

No.
12. Methods in an interface may provide a throws list?

Yes.