Building Java ProgramsChapter 10课件.ppt

Out-of-bounds Legal indexes are between 0 and the lists size() - 1. Reading or writing any index outside this range will cause an IndexOutOfBoundsException. ArrayListString names = new ArrayListString(); names.add(Marty); names.add(Kevin); names.add(Vicki); names.add(Larry); System.out.println(names.get(0)); // okay System.out.println(names.get(3)); // okay System.out.println(names.get(-1)); // exception names.add(9, Aimee); // exception index 0 1 2 3 value Marty Kevin Vicki Larry ArrayList mystery ArrayListInteger list = new ArrayListInteger(); for (int i = 1; i = 10; i++) { list.add(10 * i); // [10, 20, 30, 40, ..., 100] } What is the output of the following code? for (int i = 0; i list.size(); i++) { list.remove(i); } System.out.println(list); Answer: [20, 40, 60, 80, 100] ArrayList mystery 2 ArrayListInteger list = new ArrayListInteger(); for (int i = 1; i = 5; i++) { list.add(2 * i); // [2, 4, 6, 8, 10] } What is the output of the following code? int size = list.size(); for (int i = 0; i size; i++) { list.add(i, 42); // add 42 at index i } System.out.println(list); Answer: [42, 42, 42, 42, 42, 2, 4, 6, 8, 10] ArrayList as parameter public static void name(ArrayListType name) { Example: // Removes all plural words from the given list. public static void removePlural(ArrayListString list) { for (int i = 0; i list.size(); i++) { String str = list.get(i); if (str.endsWith(s)) { list.remove(i); i--; } } } You can also return a list: public static ArrayListType methodName(params) Exercise Write a method addStars that accepts an array list of strings as a parameter and places a * after each element. Example: if an array list named list initially stores: [the, quick, brown, fox] Then the call of addStars(list); makes it store: [the, *, quick, *, brown, *, fox, *] Write a method removeStars that accepts an array list of strings,