Vector Enumeration 示例

//Demonstrate various vector operations.
import java.util.*;
class VectorDemo{
 public static void main(String[] args)
 {
  //initial size is 3,increment is 2
  Vector v = new Vector(3,2);

  System.out.println("Initial size :" + v.size());
  System.out.println("Initial Capacity :" + v.capacity());

  v.addElement(new Integer(1));
  v.addElement(new Integer(2));
  v.addElement(new Integer(3));
  v.addElement(new Integer(4));
  System.out.println("Capacity after four additions:" + v.capacity());
  
  v.addElement(new Double(9.99));
  System.out.println("Current capacity :" + v.capacity());

  v.addElement(new Double(77.87));
  v.addElement(new Integer(9));
  System.out.println("Current capacity :" + v.capacity());

  v.addElement(new Float(77.7));
  v.addElement(new Integer(10));
  System.out.println("Current capacity :" + v.capacity());

  v.addElement(new Integer(11));
  v.addElement(new Integer(12));
  System.out.println("First element :" + (Integer)v.firstElement());
  System.out.println("Last element :" + (Integer)v.lastElement());

  if(v.contains(new Integer(3)))
  System.out.println("Vector contains 3.");

  //enumerate the elements in the vector
  Enumeration enum = v.elements();

  System.out.println("Elements in vector:");
  while(enum.hasMoreElements()){
   System.out.print(enum.nextElement() + " ");
  }
  System.out.println();

  /*
  //use an iterator to display contents
  Iterator i = v.iterator();

  System.out.println("Elements in vector:");
  while(i.hasNext()){
   System.out.print(i.next() + " ");
  }
  System.out.println();
  */
 }
}