import java.util.ArrayList;
import java.util.Iterator;

class Test {
    public static void main(String[] args) {
        ArrayList<String> a = new ArrayList<String>();
        a.add("java01");
        a.add("java02");
        a.add("java03");
        a.add("java04");
        a.add("java01");
        System.out.println(haha(a));
    }

    public static ArrayList<String> haha(ArrayList<String> a) {
        ArrayList<String> a1 = new ArrayList<String>();
        Iterator<String> t = a.iterator();
        while (t.hasNext()) {
            String v = t.next();
            if (!a1.contains(v)) {
                a1.add(v);
            }
        }
        return a1;
    }
}