vector方法

使用setElement方法象vector中添加新的引用（或者可以理解成成員）。
例如：一個碼頭，含有很多船臺，希望將一個新船臺加入碼頭中，此類：Dock
//Dock.java

package com.tianyu.summer;
import java.util.*;
public class Dock
{
 private int id;
 private String location;
 private boolean electricity;
 private boolean water;
 private Vector slips;
 public Dock(int anId,String aLocation,boolean anElectricity,boolean aWater)
 {
  setId(anId);
  setLocation(aLocation);
  setElectricity(anElectricity);
  setWater(aWater);
 }
 public void addSlipToDock(Slip aSlip)
 {
  slips.addElement(aSlip);//connect dock to slip(1...*) 
 }
 public Vector getSlips()
 {return slips;}
 public void setId(int anId)
 {id=anId;}
 public void setLocation(String aLocation)
 {location=aLocation;}
 public void setElectricity(boolean anElectricity)
 {electricity=anElectricity;}
 public void setWater(boolean aWater)
 {water=aWater;}
 
 public int getId()
 {return id;}
 public String getLocation()
 {return location;}
 public boolean getElectricity()
 {return electricity;}
 public boolean getWater()
 {return water;}
}

Vector.size()用來統計 Vector中含有多少個成員，返回int型
Vector.elementAt( i )將第i個元素返回，返回類型是Object，必須使用強制轉換