Java Collection - 如何在两个数组中查找重复值

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

public class MainClass {

  public static void main(String[] a) {
    String elements[] = { "A", "B", "C", "D", "E" };
    Set set = new HashSet(Arrays.asList(elements));

    elements = new String[] { "B", "D", "F", "G", "1", "2", "3", "4" };
    Set set2 = new HashSet(Arrays.asList(elements));

    set.retainAll(set2);

    System.out.println(set);
  }
}