MULTIPLE CHOICE QUESTIONS 1 10 4 points each For questions 1 2 below use the following partial class definitions public class C1 public int a private int b protected int c public class C2 extends C1 protected int x public int y public class C3 extends C2 private int z 1 Which of the following is true with respect to C1 C2 and C3 a C3 is a superclass of C2 and C2 is a superclass of C3 b C1 and C2 are both subclasses of C3 c C2 and C3 are both subclasses of C1 d C3 is a subclass of C2 and C2 is a subclass of C1 e None of the above 2 Which of the following lists of instance data are accessible in class C2 a x y z a b b x y a c x y a c d a y e None of the above a 1 b 2 c 4 d 8 e None of the above 3 In the following array what is the value of stats length double stats 3 00 3 50 6 35 3 4 2 7 7 35 8 35 9 00 4 Given the classes below what is the output of the following program execution public class PosNumberException extends public class Tester Exception message Sets up exception object with a particular public PosNumberException String message static public void main String args String numbers 57 fifty 50 39 PosNumberException problem new PosNumberException positive super message if Integer parseInt numbers i 0 throw problem System out print negative for int i 0 i numbers length i try catch PosNumberException e System out print e getMessage catch NumberFormatException e System out print none a none negative b positive none negative positive c negative none positive negative d positive positive e None of the above 5 Show the output of the following code public class Test5 public static void main String args int x 1 2 3 int y 3 2 3 modArrays x 0 y System out println x 0 y 0 public static void modArrays int a int b for int i 0 i b length i b i a a b 2 a 1 3 b 4 4 c 3 4 d 2 4 e None of the above 6 If the method is invoked as rose 4 what is returned public static int rose int n if n 0 return 1 else return rose n 1 n a 64 b 12 c 256 d 24 e None of the above 7 Choose the correct output of the following code fragment int arr 1 0 1 try for int i 0 i arr length i System out print 1 arr i catch ArithmeticException e System out print 0 catch ArrayIndexOutOfBoundsException e System out print out a 1 0 b 1 0 1 out c 1 0 out d 1 0 1 e None of the above 8 Abstract methods are used when defining a derived classes b classes that have no constructors c arrays d interfaces e None of the above 9 Given the following code what is the output public class Animal public class Cat extends Animal public String getColor public String getColor return color return black public class Dog extends Animal public String getColor public class Inherit public static void tryme Animal a return white System out print a getColor public static void main String args Animal a new Dog tryme a a new Cat tryme a a color black b color white c color black d white black e None of the above 10 The following method purports to be a recursive method What is the problem with it public int recurse int n int result 1 rec 2 if n 2 result n 1 rec return result a Method parameter must be a double b There is no base case c The recursive call does not move the parameter closer to the base case d Method does not call itself e None of the above 11 20 points Write a recursive method called recProd that takes two parameters array a non empty array of integers count a positive integer less than or equal to the size of array The method returns the product of count array entries For example the code fragment below would display 24 int a 1 2 3 4 5 System out println recProd a 4 12 20 points Given the Student class public class Student private int finalScore public Student int finalScore this finalScore finalScore public void setFinalScore int f finalScore f public int getFinalScore return finalScore Write ONLY the constructor for a class Course that has two attributes stdList an array of Student objects enrolled in the course stats an array of integers containing the frequencies of each A score from the array of students An A score is a score greater than 90 The constructor takes an integer parameter named size representing the array s size It initializes all the elements of the array to student objects with finalScore value a random number between 1 and 100 and populates the stats array accordingly 13 20 points Write the definition of a child class of class Figure named Line The Line class is defined by 2 point vertices attributes defined by class Point below The class should also have these members a constructor that takes two Point objects as parameters to initialize the attributes getters and setters for the class attributes a method equals that returns true of two lines have same length and false otherwise HINT Remember to define redefine any other methods needed in the child class public abstract double perimeter returns the total length between the vertices in figure public abstract class Figure protected String name public Figure String s name s public String toString return figure public class Point private int x y public Point int x int y this x x this y y public String toString return x x y y public double distance Point other return Math sqrt Math pow x other x 2 Math pow y other y 2 Question 11 Solution Question 12 Solution Question 13 Solution Quick Reference Scanner Class Scanner InputStream source Scanner File source Scanner String source String next String nextLine int nextInt double nextDouble float nextFloat String Class String String str int length int compareTo String anotherString char charAt int index boolean equals String anotherString String substring int beginIndex int endIndex String substring int beginIndex Random Class Random float nextFloat int nextInt int num int nextInt Math Class static double random static final double PI