字节流拷贝图片时间好长. - 黑马程序员技术交流社区

package cn.itcast.day;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
public class StreamTest {
public static void main(String[] args) throws IOException{
// TODO Auto-generated method stub
long start = System.currentTimeMillis();
copy();
long end = System.currentTimeMillis();
System.out.println("time = "+ (end - start));
}
public static void copy_1()throws IOException{
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("d:\\day01\\1.jpg"));
BufferedInputStream bis = new BufferedInputStream(new FileInputStream("d:\\day01\\a.jpg"));
int len = 0;
while((len = bis.read())!= -1){
bos.write(len);
bos.flush();
}
bos.close();
bis.close();
}
public static void copy()throws IOException{
FileInputStream fis = new FileInputStream("d:\\day01\\a.jpg");
My_Stream ms = new My_Stream(fis);
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("d:\\day01\\1.jpg"));
int len = 0;
//System.out.println(ms.myRead());
while((len = ms.myRead())!= -1){
bos.write(len);
bos.flush();
}
ms.myClose();
bos.close();
}
}
class My_Stream{
private InputStream ips;
private byte[] buf = new byte[1024*100];
private int len = 0;
private int count = 0;
public My_Stream(InputStream ips) {
this.ips = ips;
}
public int myRead()throws IOException{
if(len == 0){
count = 0;
len = ips.read(buf);
if(len < 0)
return -1;
byte b = buf[count];
len--;
count++;
return b&255;
}else if(len > 0){
byte b = buf[count];
len--;
count++;
return b&255;
}
return -1;
}
public void myClose()throws IOException{
ips.close();
}
}

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