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Consider the following code snippet: public static boolean isEven(int n) { if (n % 2 == 0) { return true; } else { return (isOdd(n)); } } public static boolean isOdd(int n) { if (n % 2 == 1) { return true; } else { return (isEven(n)); } } For any given value of n, what is the maximum number of function calls that could occur, including the original call?

The Comparable interface consists of a single method called ____.

Which of the following GUI objects generate(s) action events? I JComboBox II JRadioButton III JButton

Complete the following code snippet, which is intended to be a recursive method that will find the sum of all elements in an array of double values from the beginning of the array to index: // return the sum of all elements in arr[] public static double findSum(double arr[], int index) { if (index == 0) { _____________________ } else { return (arr[index] + findSum(arr, index – 1)); } } Assume that this method would be called using an existing array named myArray as follows: findSum(myArray,myArray.length – 1);

Consider the permutations method from the textbook, which is intended to return all permutations of the word passed in as a parameter. What special cases for the simplest values are used by the permutations method to terminate the recursion? public static ArrayList permutations(String word) { ArrayList result = new ArrayList(); if (word.length() == 0) // line #1 { result.add(word); // line #2 return result; // line #3 } else { for (int i = 0; i < word.length(); i++) // line #4 { String shorter = word.substring(0, i) + word(substring(i + 1); // line #5 ArrayList shorterPermutations = permutations(shorter); // line #6 for (String s : shorterPermutations) // line #7 { result.add(word.charAt(i) + s); // line #8 } } return result; // line #9 } }

Which of the following GUI objects generate(s) action events? I JComboBox II JRadioButton III JButton

Consider the permutations method from the textbook, which is intended to return all permutations of the word passed in as a parameter. How does the permutations method simplify its input for the recursive call? public static ArrayList permutations(String word) { ArrayList result = new ArrayList(); if (word.length() == 0) // line #1 { result.add(word); // line #2 return result; // line #3 } else { for (int i = 0; i < word.length(); i++) // line #4 { String shorter = word.substring(0, i) + word(substring(i + 1); // line #5 ArrayList shorterPermutations = permutations(shorter); // line #6 for (String s : shorterPermutations) // line #7 { result.add(word.charAt(i) + s); // line #8 } } return result; // line #9 } }

Which of the following arrays can be used in a call to the Arrays.sort method? I     Any array with primitive numeric data, such as int, double, … II    Arrays of String or numeric wrapper classes like, Integer, Double, … III   Any class that implements the Comparable interface

Which of the following statements about using the PrintWriter object is correct?

Suppose objects a and b are from a user-defined class that implements the Comparable interface.  What must be true about the return value of a.compareTo(b) for the compareTo method that this class implements?