list.java

Java程序设计技巧与开发实例附书源代码。

public class List {
  private int maxItems = 100;
  private int numItems = 0;
  private Object[] list = null;
  public List() {
    list = new Object[maxItems];
  }

  public List(int _maxItems) {
    maxItems = _maxItems;
    list = new Object[maxItems];
  }

  public void add(Object obj) {
    /* ASSUMES that there is room to add obj,
     *i.e. assumes that numItems < maxItems.
     */
    list[numItems] = obj;
    numItems++;
  }

  public void delete(int pos) {
    // ASSUMES that pos is between 0 and numItems
    for (int i = pos + 1; i < numItems; i++) {
      list[i - 1] = list[i];
    }
    numItems--;
  }

  public Object get(int pos) {
    return list[pos];
  }

  public int getSize() {
    return numItems;
  }

  public boolean isFull() {
    return (numItems >= maxItems);
  }

  public String toString() {
    String s = new String();
    for (int i = 0; i < numItems; i++) {
      s += "\n" + list[i].toString();
    }
    return s + "\n";
  }
}