How to sort HashSet in Java Last Updated : 11 Jul, 2025 Comments Improve Suggest changes Like Article Like Report Given a HashSet in Java, the task is to sort this HashSet. Examples: Input: HashSet: [Geeks, For, ForGeeks, GeeksforGeeks] Output: [For, ForGeeks, Geeks, GeeksforGeeks] Input: HashSet: [2, 5, 3, 1, 4] Output: [1, 2, 3, 4, 5] The HashSet class implements the Set interface, backed by a hash table which is actually a HashMap instance. No guarantee is made as to the iteration order of the set which means that the class does not guarantee the constant order of elements over time. It means that HashSet does not maintains the order of its elements. Hence sorting of HashSet is not possible. However, the elements of the HashSet can be sorted indirectly by converting into List or TreeSet, but this will keep the elements in the target type instead of HashSet type. Below is the implementation of the above approach: Program 1: By Converting HashSet to List. Java // Java program to sort a HashSet import java.util.*; public class GFG { public static void main(String args[]) { // Creating a HashSet HashSet<String> set = new HashSet<String>(); // Adding elements into HashSet using add() set.add("geeks"); set.add("practice"); set.add("contribute"); set.add("ide"); System.out.println("Original HashSet: " + set); // Sorting HashSet using List List<String> list = new ArrayList<String>(set); Collections.sort(list); // Print the sorted elements of the HashSet System.out.println("HashSet elements " + "in sorted order " + "using List: " + list); } } Output: Original HashSet: [practice, geeks, contribute, ide] HashSet elements in sorted order using List: [contribute, geeks, ide, practice] Program 2: By Converting HashSet to TreeSet. Java // Java program to sort a HashSet import java.util.*; public class GFG { public static void main(String args[]) { // Creating a HashSet HashSet<String> set = new HashSet<String>(); // Adding elements into HashSet using add() set.add("geeks"); set.add("practice"); set.add("contribute"); set.add("ide"); System.out.println("Original HashSet: " + set); // Sorting HashSet using TreeSet TreeSet<String> treeSet = new TreeSet<String>(set); // Print the sorted elements of the HashSet System.out.println("HashSet elements " + "in sorted order " + "using TreeSet: " + treeSet); } } Output: Original HashSet: [practice, geeks, contribute, ide] HashSet elements in sorted order using TreeSet: [contribute, geeks, ide, practice] Comment More infoAdvertise with us Next Article Introduction to Java R RishabhPrabhu Follow Improve Article Tags : Java Java-Collections java-hashset Java-Set-Programs Practice Tags : JavaJava-Collections Similar Reads Java Tutorial Java is a high-level, object-oriented programming language used to build web apps, mobile applications, and enterprise software systems. 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