public static int[] toIntArray(Collection<Integer> items) {
		int[] result = new int[items.size()];
		int i = 0;
		for (Integer v : items) {
			result[i++] = v;
		}
		return result;
	}
public static int[] toIntArray(Collection<Integer> items) {
		int[] result = new int[items.size()];
		int i = 0;
		for (Integer v : items) {
			result[i++] = v;
		}
		return result;
	}
public static int [ ] toIntArray ( Collection < Integer > items ) { int [ ] result = new int [ items . size ( ) ] ; int i = 0 ; for ( Integer v : items ) { result [ i ++ ] = v ; } return result ; }
Convert a collection of Integers into an int array.

@param items
@return
Convert a collection of Integers into an int array .