Java™ How To Program (Early Objects), Tenth Edition

16.9 Class PriorityQueue and Interface Queue

Recall that a queue is a collection that represents a waiting line—typically, insertions are made at the back of a queue and deletions are made from the front. In Section 21.6, we’ll discuss and implement a queue data structure. In this section, we investigate Java’s Queue interface and PriorityQueue class from package java.util. Interface Queue extends interface Collection and provides additional operations for inserting, removing and inspecting elements in a queue. PriorityQueue, which implements the Queue interface, orders elements by their natural ordering as specified by Comparable elements’ compareTo method or by a Comparator object that’s supplied to the constructor.

Class PriorityQueue provides ...