SortedSet is a child interface of Set Interface. It exhibits similar behaviour to its parent interface like not allowing duplicates and not preserving insertion order. As its name suggests, the elements present in sortedSet, are always stored in sorting order. By default, it applies natural sorting to arrange the elements in a specific order. For example, in the case of numbers, the elements are sorted in ascending order, and in the case of strings, in alphabetical order. It is implemented by ConcurrentSkipListSet and TreeSet classes.
Further, it supports several additional methods that are only applicable to its implementing classes. first(), last(), and comparator() are some of the methods.
In other words, SortSet is an interface that is used to store a collection of elements in some specific order. It uses the compareTo() method, which is present in the Comparable interface and compare() method, which exists in the Comparator interface, to define sorting order. For natural sorting, by default, it uses the compareTo() method whereas, compare() is used to generate custom ordering of elements.
TreeSet is an implementation class of SortedSet that exhibits self-balancing binary tree as its underlying data structure. It provides a way to store elements and retrieve elements in a sorted manner. The elements that are added in a TreeSet instance, get sorted automatically.
Syntax:
SortedSet<T> set = new TreeSet<T>();
SortedSet provides various methods such as first() method that returns the first element of a set, the last() method that returns the last element of a set, and the subSet() method that returns a portion of the set that falls within a specified range.
Point to Remember
How to create an object of SortedSet?
SortedSet is an interface whose implementation class is TreeSet. With the help of implementation classes, we can assign its instance to sortedSet interface. Below is the example:
Program:
import java.util.*;
public class SetExample {
public static void main(String[] args) {
SortedSet<String> sortedSet = new TreeSet<>() ; // Creating sortedSet object
// Adding elements to sorted set object
sortedSet.add("Example");
sortedSet.add("Code");
sortedSet.add("A");
// Displaying the output
System.out.println(sortedSet);
// Removing A element from the set
sortedSet.remove("A");
System.out.println(sortedSet);
// printing first element from the set
System.out.println(sortedSet.first());
// printing last element from the set
System.out.println(sortedSet.last());
}
}Output:
[A, Code, Example] [Code, Example] Code Example
