java list without duplicate code example

Example 1: java remove duplicates

import java.util.*;

public class RemoveDuplicatesFromArrayList {

    public static void main(String[] args) {
        List<Integer> numbers = Arrays.asList(1,2,2,2,3,5);

        System.out.println(numbers);

        Set<Integer> hashSet = new LinkedHashSet(numbers);
        ArrayList<Integer> removedDuplicates = new ArrayList(hashSet);

        System.out.println(removedDuplicates);
    }
}

Example 2: java remove duplicates

public static <T> ArrayList<T> removeDuplicates(ArrayList<T> list){
  Set<T> set = new LinkedHashSet<>(list);
  return new ArrayList<T>(set);
}

Example 3: compare two lists and remove duplicates java

listA.removeAll(new HashSet(listB));

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Java Example