shiyan.java

处理异常需要的时间开销因方法不同

import java.util.Date;
import java.util.Vector;

public class Shiyan
{
    public static void J_Method1()
    {
        int N=10000;
        Integer[] iarr1 = new Integer[0];
        Date d1=new Date();
        for(int i=0; i<N; i++)
        {
            try
            {
                iarr1[i] = new Integer(i);
            }
            catch(ArrayIndexOutOfBoundsException e)
            {
                Integer[] newArr = new Integer[iarr1.length+1];
                for(int j =0; j<iarr1.length; j++)
                {
                    newArr[j] = iarr1[j];
                    //newArr[iarr1.length] = new Integer(i);
                    //iarr1 = newArr;
                }
                newArr[iarr1.length]=new Integer(iarr1.length);
                iarr1=newArr;
             }
        }
        Date d2=new Date();
        long t=d2.getTime()-d1.getTime();
        System.out.printf("利用方法1处理异常需要的时间开销为:%1$dms%n",t);
    }

    public static void J_Method2()
    {
        int N=10000;
        Integer[] iarr2 = new Integer[N];
        Date d1=new Date();
        for(int i=0; i<N; i++)
       
            
            {
                iarr2[i] = new Integer(i);
            }
          
        Date d2=new Date();
        long t=d2.getTime()-d1.getTime();
        System.out.printf("利用方法2处理异常需要的时间开销为:%1$dms%n",t);
    }

    public static void J_Method3()
    {
         Vector<Integer> iarr3=new Vector<Integer>();
         int N=100000;
         Date d1=new Date();
         for(int i=0; i<N; i++)
        {
             iarr3.add(new Integer(i));                       
        }
         Date d2=new Date();
         long t=d2.getTime()-d1.getTime();
         System.out.printf("方法3中向向量添加元素需要的时间开销为:%1$dms%n",t);
    }
    
    public static void main(String[] args)
    {
       J_Method1();
       J_Method2();
       J_Method3();
    }
}