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  1. Given:
    public abstract interface Frobnicate {
        public void twiddle(String s);
    }
    Which is a correct class? (Choose all that apply.)
  2. Given:
    class Top {
        public Top(String s) {
            System.out.print("B");
        }
    }

    public class Bottom2 extends Top {
        public Bottom2(String s) {
            System.out.print("D");
        }

        public static void main(String[] args) {
            new Bottom2("C");
            System.out.println(" ");
        }
    }
    What is the result?
  3. Given:
    class Clidder {
        private final void flipper() {
            System.out.println("Clidder");
        }
    }

    public class Clidlet extends Clidder {
        public final void flipper() {
            System.out.println("Clidlet");
        }

        public static void main(String[] args) {
            new Clidlet().flipper();
        }
    }
    What is the result:
  4. Use the fragments below, complete the following code so it compiles. Note, you may not have to fill all of the slots.
    Code:
    class AgedP {
        __________ __________ __________ __________ __________

        public AgedP(int x) {
            __________ __________ __________ __________ __________
        }
    }

    public class Kinder extends AgedP {
        __________ __________ __________ _________ ________ __________

        public Kinder(int x) {
            __________ __________ __________ __________ __________ ();
        }
    }
    Fragments: Use the following fragments zero or more times:
    AgedP super this
    ( ) { }
    ;
  5. Given the following,
    1.  class X { void do1() { } }
    2.  class Y extends X { void do2() { } }
    3. 
    4.  class Chrome {
    5.     public static void main(String[] args) {
    6.          X x1 = new X();
    7.          X x2 = new Y();
    8.          Y y1 = new Y();
    9.          // insert code here
    10.     } }
    Which, inserted at line 9, will compile? (Choose all that apply.)
  6. Given:
    3.  class Dog {
    4.      public void bark() { System.out.print("woof "); }
    5.  }
    6.  class Hound extends Dog {
    7.      public void sniff() { System.out.print("sniff "); }
    8.      public void bark() { System.out.print("howl "); }
    9.  }
    10. public class DogShow {
    11.     public static void main(String[] args) { new DogShow().go(); }
    12.     void go() {
    13.         new Hound().bark();
    14.         ((Dog) new Hound()).bark();
    15.         ((Dog) new Hound()).sniff();
    16.     }
    17. }
    What is the result? (Choose all that apply.)
  7. Given:
    3.  public class Redwood extends Tree {
    4.      public static void main(String[] args) {
    5.          new Redwood().go();
    6.      }
    7.      void go() {
    8.          go2(new Tree(), new Redwood());
    9.          go2((Redwood) new Tree(), new Redwood());
    10.     }
    11.     void go2(Tree t1, Redwood r1) {
    12.         Redwood r2 = (Redwood) t1;
    13.         Tree t2 = (Tree) r1;
    14.     }
    15. }
    16. class Tree {}
    What is the result? (Choose all that apply.)
  8. Given:
    3.  public class Tenor extends Singer {
    4.      public static String sing() { return "fa"; }
    5.      public static void main(String[] args) {
    6.          Tenor t = new Tenor();
    7.          Singer s = new Tenor();
    8.          System.out.println(t.sing() + " " + s.sing());
    9.      }
    10. }
    11. class Singer { public static String sing() { return "la"; } }
    What is the result?
  9. Given:
    3.  class Alpha {
    4.      static String s = " ";
    5.      protected Alpha() { s += "alpha "; }
    6.  }
    7.  class SubAlpha extends Alpha {
    8.      private SubAlpha() { s += "sub "; }
    9.  }
    10. public class SubSubAlpha extends Alpha {
    11.     private SubSubAlpha() { s += "subsub "; }
    12.     public static void main(String[] args) {
    13.         new SubSubAlpha();
    14.         System.out.println(s);
    15.     }
    16. }
    What is the result?
  10. Given:
    3.  class Building {
    4.      Building() { System.out.print("b "); }
    5.      Building(String name) {
    6.          this(); System.out.print("bn " + name);
    7.      }
    8.  }
    9.  public class House extends Building {
    10.     House() { System.out.print("h "); }
    11.     House(String name) {
    12.         this(); System.out.print("hn " + name);
    13.    }
    14.     public static void main(String[] args) { new House("x "); }
    15. }
    What is the result?
  11. Given:
    3.  class Mammal {
    4.      String name = "furry ";
    5.      String makeNoise() { return "generic noise"; }
    6.  }
    7.  class Zebra extends Mammal {
    8.      String name = "stripes ";
    9.      String makeNoise() { return "bray"; }
    10. }
    11. public class ZooKeeper {
    12.     public static void main(String[] args) { new ZooKeeper().go(); }
    13.     void go() {
    14.         Mammal m = new Zebra();
    15.         System.out.println(m.name + m.makeNoise());
    16.     }
    17. }
    What is the result?
  12. You're designing a new online board game in which Floozels are a type of Jammers, Jammers can have Quizels, Quizels are a type of Klakker, and Floozels can have several Floozets. Which of the following fragments represent this design? (Choose all that apply.)
  13. Given:
    3.  class A { }
    4.  class B extends A { }
    5.  public class ComingThru {
    6.      static String s = "-";
    7.      public static void main(String[] args) {
    8.          A[] aa = new A[2];
    9.          B[] ba = new B[2];
    10.         sifter(aa);
    11.         sifter(ba);
    12.         sifter(7);
    13.         System.out.println(s);
    14.     }
    15.     static void sifter(A[]... a2) { s += "1"; }
    16.     static void sifter(B[]... b1) { s += "2"; }
    17.     static void sifter(B[] b1) { s += "3"; }
    18.     static void sifter(Object o) { s += "4"; }
    19. }
    What is the result?
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