text: public int indexOf(Object object) {int pos = 0;Link<E> link = voidLink.next;if (object != null) {while (link != voidLink) {if (object.equals(link.data)) {return pos;}link = link.next;pos++;}} else {while (link != voidLink) {if (link.data == null) {return pos;}link = link.next;pos++;}}return -1;}