Thread: Need Help on testing Code

The following is the code that I have written so far for an assignment. I am having difficulty testing my methods so far. In the main method, I try to create a SimpleSet setA = new SimpleSet() but I keep getting an error. Can anyone help me? Thank you.

	import java.util.*; 
 
public class SimpleSet<K extends Comparable<? super K>>{ 
 
	/* use SimpleSortedDictionary object to hold set items
   Note: Value is not needed, just set it to Boolean */ 
	private DictionaryInterface<K, Boolean> items; 
 
	/* default constructor */ 
	public SimpleSet() {
		items = new SimpleSortedDictionary<K, Boolean>();
	}
 
	/* Adds a given object to the set. If the given object already exists in the set, 
	    return false; otherwise, return true */ 
	public boolean add(K item){
		boolean result;
		if(items.add(item, true) != null) 
		{
			result = true;
		}else result = false;
		return result;
	}
 
	/* Removes a given object from the set. */ 
	public void remove(K item){
		this.items.remove(item);
	}
 
	/* Sees whether the set contains a given object. */ 
	public boolean contains(K item){
		return this.items.contains(item);
	}
 
	/* Clears all objects from the set. */ 
	public void clear(){
		items.clear();
	}
 
	/* Gets the number of objects in the set. */ 
	public int getSize(){
		return items.getSize();
	}
 
	/* Returns an iterator to the set. */ 
	public Iterator<K> getIterator(){
		return items.getKeyIterator();
	}
 
 
        /* may define tests here */ 
	public static void main(String args[]) {
		SimpleSet setA = new SimpleSet<K>();
		int five = 5;
		setA.add(five);
		System.out.print(setA);
		//SimpleSet setA = new SimpleSet();
		//SimpleSet setA = new SimpleSortedDictionary();
		//Integer five = new Integer(5);
		//setA.add(five);
		//setA.toString();
 
 
	}
 
	}
} // end SimpleSet