第四次作业 文件复制速度的提升

package proj;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class Copy {
public static void main(String []args){
try {
FileInputStream fis =new FileInputStream("a.mp3");
FileOutputStream fos =new FileOutputStream("a.mp3");
int read=fis.read();

while(read !=-1){
fos.write(read);
read=fis.read();
}
fis.close();
fos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
long endTime = System.currentTimeMillis();
long startTime = 0;
System.out.println("用时: " + (endTime - startTime) + " ms");

}

}

byte[] buf = new byte[1024];
int len = 0 ;//提高读取字节速度

while((len=fis.read(buf)) != -1){
fos.write(buf,0,len);}