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8. OOPs
Q: 47 Given: 11. static class A { 12. void process() throws Exception { throw new Exception(); } 13. } 14. static class B extends A { 15. void process() { System.out.println("B"); } 16. } 17. public static void main(String[] args) { 18. new B().process(); 19. } What is the result? A. B B. The code runs with no output. C. Compilation fails because of an error in line 12. D. Compilation fails because of an error in line 15. E. Compilation fails because of an error in line 18. Answer: A Q: 48 Given: 11. class ClassA {} 12. class ClassB extends ClassA {} 13. class ClassC extends ClassA {} and: 21. ClassA p0 = new ClassA(); 22. ClassB p1 = new ClassB(); 23. ClassC p2 = new ClassC(); 24. ClassA p3 = new ClassB(); 25. ClassA p4 = new ClassC(); Which three are valid? (Choose three.) A. p0 = p1; B. p1 = p2; C. p2 = p4; D. p2 = (ClassC)p1; E. p1 = (ClassB)p3; F. p2 = (ClassC)p4; Answer: A, E, F Q: 49 Given: 11. abstract class Vehicle { public int speed() { return 0; } 12. class Car extends Vehicle { public int speed() { return 60; } 13. class RaceCar extends Car { public int speed() { return 150; } ... 21. RaceCar racer = new RaceCar(); 22. Car car = new RaceCar(); 23. Vehicle vehicle = new RaceCar(); 24. System.out.println(racer.speed() + ", " + car.speed() 25. + ", " + vehicle.speed()); What is the result? A. 0, 0, 0 B. 150, 60, 0 C. Compilation fails. D. 150, 150, 150 E. An exception is thrown at runtime. Answer: D Q: 50 Given code in separate source files: 10. public class Foo { 11. public int a; 12. public Foo() { a = 3; } 13. public void addFive() { a += 5;} 14. } and: 20. public class Bar extends Foo { 21. public int a; 22. public Bar() { a = 8; } 23. public void addFive() { this.a += 5; } 24. } invoked with: 30. Foo foo = new Bar(); 31. foo.addFive(); 32. System.out.println("Value: " + foo.a); What is the result? A. Value: 3 B. Value: 8 C. Value: 13 D. Compilation fails. E. The code runs with no output. F. An exception is thrown at runtime. Answer: A
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