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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?

Which sort algorithm starts by partitioning the array and selecting a pivot element?

Assuming that names is a Queue of String objects, select a statement to complete the code segment below.  The code is designed to remove the last element from the queue, which is guaranteed to have at least one element. Queue aQueue = new LinkedList(); while (names.size() > 1) { aQueue.add(names.remove()); } names.remove(); while (aQueue.size() > 0) { ____________________________ }