remove duplicates from list in java using set

Hi,

The Set interface in Java is part of Collection API which does not allow the duplicate elements.

Here is example code to remove duplicates from list in java using set:

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

public class RemoveDuplicatesWithSet {

    public static void main(String[] args) {
        // Define array list
        List<String> daysList = Arrays
                .asList(new String[] { "Sunday", "Monday", "Tuesday", "SUNDAY", "MONDAY", "TUESDAY" });
        //Create set object with CASE_INSENSITIVE_ORDER feature
        Set<String> uniqueSet = new TreeSet<String>(String.CASE_INSENSITIVE_ORDER);

        //Add list to the set - Set will add only unique values
        uniqueSet.addAll(daysList);

        for (String day : uniqueSet) {
            System.out.println(day);
        }

    }

}

Thanks

Hi,

You can convert the set object back to list with following example code:

List<String> list = new ArrayList<>(uniqueSet);

Thanks

Hi,

This is another example:

• Remove duplicates from ArrayList

Thanks