public boolean add(Object element) 
{
        return getIntCollection().add(((Number)element).intValue());
}

 public boolean addAll(Collection c) 
{
        return getIntCollection().addAll(CollectionIntCollection.wrap(c));
}

 public  void clear() 
{
        getIntCollection().clear();
}

 public boolean contains(Object element) 
{
        return getIntCollection().contains(((Number)element).intValue());
}

 public boolean containsAll(Collection c) 
{
        return getIntCollection().containsAll(CollectionIntCollection.wrap(c));
}

 abstract protected IntCollection getIntCollection()

 public boolean isEmpty() 
{
        return getIntCollection().isEmpty();
}

 public Iterator iterator() 
{
        return IntIteratorIterator.wrap(getIntCollection().iterator());
}

wraps the IntIterator returned by my underlying IntCollection , if any.

 public boolean remove(Object element) 
{
        return getIntCollection().removeElement(((Number)element).intValue());
}

 public boolean removeAll(Collection c) 
{
        return getIntCollection().removeAll(CollectionIntCollection.wrap(c));
}

 public boolean retainAll(Collection c) 
{
        return getIntCollection().retainAll(CollectionIntCollection.wrap(c));
}

 public int size() 
{
        return getIntCollection().size();
}

 public Object[] toArray() 
{
        int[] a = getIntCollection().toArray();
        Object[] A = new Object[a.length];
        for(int i=0;i< a.length;i++) {
            A[i] = new Integer(a[i]);
        }
        return A;
}

 public Object[] toArray(Object[] A) 
{
        int[] a = getIntCollection().toArray();
        if(A.length <  a.length) {
            A = (Object[])(Array.newInstance(A.getClass().getComponentType(), a.length));
        }
        for(int i=0;i< a.length;i++) {
            A[i] = new Integer(a[i]);
        }
        if(A.length  > a.length) {
            A[a.length] = null;
        }
        return A;
}

 public String toString() 
{
        return getIntCollection().toString();
}