Vector Enumeration 示例

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原创最新推荐文章于 2026-05-21 05:55:13 发布 1.2k 阅读 AI 写同款· GEO 优化 ›

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//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();
  */
}
}