Day 24: Removing nulls from list using Collections.singleton and Objects.isNull

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import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;

class Day24 {
    public static void main(String[] args) {
        String[] filesFromDirUsr = {"A.txt", "C.txt", null, "G.txt"};
        List<String> usrFiles = new ArrayList<>(Arrays.asList(filesFromDirUsr));

        String[] fileFromDirDownloads = {"X.txt", null, "J.txt", "N.txt", null, null};
        List<String> downloadedFiles = new ArrayList<>(Arrays.asList(fileFromDirDownloads));

        usrFiles.forEach(System.out::println);
        downloadedFiles.forEach(System.out::println);

        usrFiles.removeAll(Collections.singleton(null));
        downloadedFiles.removeIf(Objects::isNull);
        System.out.println();

        usrFiles.forEach(System.out::println);
        downloadedFiles.forEach(System.out::println);
    }
}