To keep the unique value of a large data set, Set would be a good option. Every element in a set is unique, when a duplicate element is added, it is ignored.
Here is a sample code from oracle.
public class FindDups2 { public static void main(String[] args) { Set<String> uniques = new HashSet<String>(); Set<String> dups = new HashSet<String>(); for (String a : args) if (!uniques.add(a)) dups.add(a); // Destructive set-difference uniques.removeAll(dups); System.out.println("Unique words: " + uniques); System.out.println("Duplicate words: " + dups); } } |