TreeSet : subSet(), isEmpty(), pollFirst()

The subSet() methods returns a view of the portion of this set whose elements range from fromElement, inclusive, to toElement, exclusive. The isEmpty() methods returns true if this set contains no elements. The pollFirst() methods retrieves and removes the first (lowest) element, or returns null if this set is empty. Program       Program Source import java.util.TreeSet; public class Javaapp … Read more…

Java TreeSet : ceiling(), floor(), headSet(), tailSet()

The ceiling() method returns the least element in this set greater than or equal to the given element, or null if there is no such element. The floor() method returns the greatest element in this set less than or equal to the given element, or null if there is no such element. The headset() method returns a view of … Read more…

TreeSet : first(), last(), lower(), higher(), descendingSet()

The first() method returns the first (lowest) element currently in this set. The last() method returns the last (highest) element currently in this set. The lower() method returns the greatest element in this set strictly less than the given element, or null if there is no such element. The higher() method returns the least element in this … Read more…

Java TreeSet

TreeSet extends AbstractSet and implements the NavigableSet interface. It creates a collection that uses a tree for storage. Objects are stored in sorted, ascending order. Access and retrieval times are quite fast, which makes TreeSet an excellent choice when storing large amounts of sorted information that must be found quickly. TreeSet has the following constructors: … Read more…

Java HashSet : size() contains() remove() clear()

The remove() method shall be used to remove an unwanted object from a collection. We shall use the clear() method to completely empty a collection. The Contains() method enables us to determine whether a specific object is present in a collection or not. The size() method returns the number of elements in a collection. The … Read more…

Java HashSet

The Hashset class extends the AbstractSet class. The HashSet class implements the Set interface. This class deals with a collection, whose elements are stored in a hash table. The hashing mechanism is used to store the elements in a hash table. This mechanism uses the informational content of a key to determine a unique value. … Read more…