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How to remove duplicate element from array?

This example demonstrate you how to remove duplicate elements from an array using the HashSet class.

package com.javacoderanch.example.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 it to list as we need the list object to create a set object.
        // A set is a collection object that cannot have a duplicate values, so
        // by converting the array to a set the duplicate value will be removed.
        List<String> list = Arrays.asList(data);
        Set<String> set = new HashSet<String>(list);

        System.out.print("Remove duplicate result: ");
        // Create an array to convert the Set back to array. The Set.toArray()
        // method copy the value in the set to the defined array.
        String[] result = new String[set.size()];
        for (String s : result) {
            System.out.print(s + ", ");