JAVA Geneic Programming

public class Generic<T> {
	
	public Generic() {
		head = null;
		tail = null;
	}
	public Generic(T head, T tail) {
		this.head = head;
		this.tail = tail;
	}

	public T getHead() {
		return head;
	}
	public void setHead(T head) {
		this.head = head;
	}
	public T getTail() {
		return tail;
	}
	public void setTail(T tail) {
		this.tail = tail;
	}
	
	private T head;
	private T tail;
}

public class GenericTest {

	public static <T extends Comparable> Generic<T> minmax(T[] a) {
		if (a == null || a.length == 0) {
			return null;
		}
		T max = a[0];
		T min = a[0];

		for (int i = 1; i < a.length; i++) {
			if (min.compareTo(a[i]) > 0) {
				min = a[i];
			}

			if (max.compareTo(a[i]) < 0) {
				max = a[i];
			}
		}
		return new Generic<T>(min, max);
	}

	public static void main(String[] args) {
		
		GregorianCalendar[] date = {
				new GregorianCalendar(1903,Calendar.FEBRUARY,9),
				new GregorianCalendar(1815,Calendar.JUNE,18),
				new GregorianCalendar(1910,Calendar.JULY,9),
		};
		
		Generic<GregorianCalendar> gg = minmax(date);
		System.out.println(gg.getHead().getTime()+"\n"+gg.getTail().getTime());
		
		/*String[] words = { "Marry", "Jim", "Xie", "littlep" };
		Generic<String> mm = minmax(words);
		System.out.println("min = " + mm.getHead() + "\n" + "max = "
				+ mm.getTail());*/
	}
}