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Which data structure would best be used for keeping track of groceries to be purchased at the food market?

Consider the permutations method from the textbook, which is intended to return all permutations of the word passed in as a parameter. Which line contains the recursive call in the permutations method? 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 } }

Select an appropriate expression to complete the following method, which is designed to visit the elements in theList and replace each occurrence of the string “hello” with the string “goodbye”. public static void helloGoodbye(LinkedList theList) { ListIterator iterator = theList.listIterator(); while (iterator.hasNext()) { if (iterator.next().equals(“hello”)) { _____________________________ } } }

With a few exceptions, what access should instance variables of classes always have?

What reserved word in a method definition ensures that subclasses cannot override the method?

Consider the following code snippet: public class Coin { private String name; . . . public boolean equals(Object otherCoin) { return name.equals(otherCoin.name); } . . . } What is wrong with this code?

Consider the code snippet shown below: Stack words1 = new Stack(); Stack words2 = new Stack(); words1.push(“abc”); words1.push(“def”); words1.push(“ghi”); while (!words1.empty()) { words2.push(words1.pop()); } while (!words2.empty()) { System.out.print(words2.pop()); } What will be printed when this code is executed?

Consider the code snippet shown below: Stack words1 = new Stack(); Stack words2 = new Stack(); words1.push(“abc”); words1.push(“def”); words1.push(“ghi”); while (!words1.empty()) { words2.push(words1.pop()); } while (!words2.empty()) { System.out.print(words2.pop()); } What will be printed when this code is executed?

Which of the following statements about superclasses and subclasses is true?

Consider the following code snippet: Vehicle aVehicle = new Auto(); aVehicle.moveForward(200); Assume that the Auto class inherits from the Vehicle class, and both classes have an implementation of the moveForward method with the same set of parameters and the same return type. What determines which class’s moveForward method is to be executed?