fixed testclass

public class SinglyTestClass
{
  public static void main()
  {
    SinglyLinkedList test = new SinglyLinkedList();
    System.out.println(test);
    test.add("one");
    test.add("two");
    test.add("three");
    test.add("four");
    System.out.println(test);
    System.out.println(test.indexOf("two"));
    System.out.println(test.get(2));
    System.out.println(test.size());
    if(test.contains("four"))
      System.out.println("contains = true");
    if(!test.contains("five"))
      System.out.println("contains = false");
    test.remove("three");
    System.out.println(test);
    test.remove(1);
    System.out.println(test);
    System.out.println(test.set(1, "two"));
    System.out.println(test);
    test.add(1, "four");
    System.out.println(test);
    test.add(1, "three");
    System.out.println(test);
  }
}