f you have taken a course on data structures in your computer science curriculum, you have used collections. In our earlier chapters, we used the Vector class and ArrayList. These classes are nothing but a part of the Collections framework. A collection is simply an object that groups multiple objects into a single unit, making it easier to perform group operations on them, to search quickly through thousands of sorted items, to insert and remove elements in the middle of an ordered sequence, and so on. Collections store and ...