exo2/ListExtension.java

   1 import java.util.List;
   2 import java.util.ListIterator;
   3
   4 public class ListExtension<E> {
   5     private List<E> list;
   6
   7     public ListExtension() {
   8         setList(null);
   9     }
  10
  11     public ListExtension(List<E> l) {
  12         setList(l);
  13     }
  14
  15     /**
  16      * [setList description]
  17      * @param l [description]
  18      */
  19     public void setList(List<E> l) {
  20         list = l;
  21     }
  22
  23     /**
  24      * [getList description]
  25      * @return [description]
  26      */
  27     public List<E> getList() {
  28         return list;
  29     }
  30
  31     public boolean add(E e) {
  32         return list.add(e);
  33     }
  34
  35     /**
  36      * Should mimic the List<E> add(int index, T value) method
  37      * @param  value [description]
  38      * @return       [description]
  39      */
  40     public void addMiddleIter(E value) {
  41         int mid = list.size() / 2;
  42         ListIterator<E> iter = list.listIterator();
  43         int i = 0;
  44         // go to the element at mid index
  45         while (iter.hasNext() && i < mid) {
  46             iter.next();
  47             i++;
  48         }
  49         iter.next(); // Insert before mid + 1
  50         iter.add(value);
  51     }
  52
  53     public void addNEMiddle(int Nelements) {
  54         ListIterator<E> iter = list.listIterator();
  55         int i = 0;
  56         // go to the element at the middle index
  57         while (iter.hasNext() && i < list.size() / 2) {
  58             iter.next();
  59             i++;
  60         }
  61         iter.next(); // Insert before mid + 1
  62         for (int j = 0; j < Nelements; j++) {
  63             iter.add((E)new Object());
  64         }
  65     }
  66
  67 }