Interfaces and Abstract Classes -Java Programming MCQ Questions and Answers

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11. 
interface Base{
      boolean m1 ();
      byte m2(short s);
}
which two code fragments will compile? 
1. interface Base2 implements Base {}

2. abstract class Class2 extends Base
    { public boolean m1(){ return true; }}

3. abstract class Class2 implements Base {}

4. abstract class Class2 implements Base
    { public boolean m1(){ return (7 > 4); }}

5. abstract class Class2 implements Base
    { protected boolean m1(){ return (5 > 7) }}

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12.
Which two of the following are legal declarations for abstract classes and interfaces?
1. final abstract class Test {}
2. public static interface Test {}
3. final public class Test {}
4. protected abstract class Test {}
5. protected interface Test {}
6. abstract public class Test {}

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13. 
interface Test{
      int p = 10; //line 1
      public int q = 20; //line 2
      public static int r = 30; //line 3
      public static final int s = 40; //line 4
}
Which of the above line will give compilation error?

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14.
What will happen after compiling this program code? 
abstract class MyClass{ //line 1
      private int a, b;

      public void call(int a, int b){
            this.a = a;
            this.b = b;
            System.out.print(a+b);
      }
}

public class Test{
      public static void main(String args[]){
            MyClass m = new MyClass(); //line 2
            m.call(12,25);
      }
}

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