Arrays

Arrays Java 2 added a new class or java.util called Arrays. This class provides various methods that <Ire useful when working with <arrays, Although these methods technically aren't part of Collections framework, they help bridge the gap between collections and...

Using a Comparator

Using a Comparator The following is an example that demonstrates the power of a custom comparator. II implements the compare() method so that i operates in reverse of normal. Thus, it causes a tree set to be stored in reverse order. As the following output shows, the...

Comparators

Comparators   Doth TreeSet and TreeMap store elements in sorted order. However, it is the. comparator that defines precisely what "sorted order" means. By default, these classes store their elements by using what Java refers to as "natural ordering," which is usually...

The TreeMap Class

The TreeMap Class TIle TrecMap class implements the Map interface by using a tree. A TreeMap provides an efficient means.of storing key value pairs in sorted order, and allows rapid retrieval. You should note that, unlike a hash map, a tree map guarantees that...

The Map Classes

The Map Classes Several classes provide implementations of the map interfaces. The classes that can be used for maps are summarized here: Notice that AbstractMap is a superclass rortne three cor-crete map Implementations. Weak HashMap implements a map that uses "weak...

The Sorted Map Interface ,

The Sorted Map Interface , The"SortedMap interface extends Map. It ensures that the entries are maintained in ascending key order. The methods declared by SortedMap are summarized in . several methods throw a NoSuchElementException when no items are in the invoking...