This example demonstrates you how to remove duplicate elements from an array using the help of java.util.HashSet class.

package org.kodejava.util;

import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public class ArrayRemoveDuplicate {
    public static void main(String[] args) {
        // A string array with duplicate values.
        String[] data = {"A", "C", "B", "D", "A", "B", "E", "D", "B", "C"};
        System.out.println("Original array         : " + Arrays.toString(data));

        // Convert a string array into java.util.List because we need a list
        // object to create the java.util.Set object.
        List<String> list = Arrays.asList(data);

        // A set is a collection object that cannot have a duplicate values,
        // by converting the array to a set the duplicate value will be removed.
        Set<String> set = new HashSet<>(list);

        // Convert the java.util.Set back to array using the toArray() method of
        // the set object copy the value in the set to the defined array.
        String[] result = set.toArray(new String[0]);
        System.out.println("Array with no duplicate: " + Arrays.toString(result));
    }
}

The result of the code snippet above:

Original array         : [A, C, B, D, A, B, E, D, B, C]
Array with no duplicate: [A, B, C, D, E]

• Author
• Recent Posts

Wayan

Founder at Kode Java Org

A programmer, recreational runner and diver, live in the island of Bali, Indonesia. Programming in Java, Spring, Hibernate / JPA. You can support me working on this project, buy me a cup of coffee ☕ every little bit helps, thank you 🙏

Latest posts by Wayan (see all)

• How do I create a string of repeated characters? - September 1, 2023
• How do I convert datetime string with optional part to a date object? - August 28, 2023
• How do I split large excel file into multiple smaller files? - April 15, 2023