public class 使用缓存区 {
public static void main(String argss[])throws FileNotFoundException,IOException
{
int c;
long time1,time2;
long time3,time4;
FileInputStream fin1=new FileInputStream(new File("hello1.txt"));
FileOutputStream fout1=new FileOutputStream(new File("hello.txt"));
time1=System.currentTimeMillis();
        while((c=fin1.read())!=-1)
{

fout1.write(c);

}
time2=System.currentTimeMillis();
System.out.println("直接复制所用的时间是"+(time2-time1));
fout1.close();fin1.close();

FileInputStream fin3=new FileInputStream(new File("hello1.txt"));
FileOutputStream fout3=new FileOutputStream(new File("hello.txt"));
BufferedInputStream fin2=new BufferedInputStream(fin3);
BufferedOutputStream fout2=new BufferedOutputStream(fout3);
time3=System.currentTimeMillis();
while((c=fin2.read())!=-1)
{

fout2.write(c);

}fout2.flush();
time4=System.currentTimeMillis();
System.out.println("缓存区复制所用的时间是"+(time4-time3));

fin2.close();
fout2.close();

}
}这个程序运行的结果为0
怎么会时间为0呢?
哪里写错了吗?