复制图片文件大家来看看问题在哪儿
import   java.io.*;
public   class   Test   {
public   static   void   main(String[]   args)   throws   Exception   {
Stream   s   =   new   Stream();
s.readjpg();
s.writejpg();
}
}

class   Stream   {
StringBuffer   sb;
Stream()   {
sb   =   new   StringBuffer();
}
void   writejpg()   throws   Exception   {
File   f   =   new   File( "obj.jpg ");
f.createNewFile();
FileOutputStream   fos   =   new   FileOutputStream(f);
DataOutputStream   dos   =   new   DataOutputStream(fos);
OutputStreamWriter   osw   =   new   OutputStreamWriter(dos);
BufferedWriter   bw   = new   BufferedWriter(osw);
String[]   str   =   sb.toString().split( "\n ");
System.out.println(str.length);
for(int   i=0;i <str.length;i++)   {
bw.write(str[i]);
bw.newLine();
}
bw.flush();
bw.close();
osw.close();
dos.close();
fos.close();
}

void   readjpg()   throws   Exception   {
int   i=1;
FileInputStream   fis   =   new   FileInputStream( "1.jpg ");
DataInputStream   dis   =   new   DataInputStream(fis);
InputStreamReader   isd   =   new   InputStreamReader(dis);
BufferedReader   br   = new   BufferedReader(isd);
while(br.readLine()!=null)   {
sb.append(br.readLine());
sb.append( "\n ");
System.out.println(i++);
}
br.close();
isd.close();
dis.close();
fis.close();
}
}

运行后为什么目标文件什么也看不到？

------解决方案--------------------
你怎么把它当成文本文件在读写哦.只要一个FileInputStream和FileOutputStream就行了.
import java.io.*;

public class Test {
public static void main(String[] args) throws Exception {
Stream s = new Stream();
s.readjpg( "qd.swf ");
s.writejpg( "b.swf ");
}
}

class Stream {
byte[] b;
Stream() {
}

void writejpg(String filename) throws Exception {
File f = new File(filename);
f.createNewFile();
FileOutputStream fos = new FileOutputStream(f);
fos.write(b);
fos.close();
}

void readjpg(String filename) throws Exception {
int i = 1;
FileInputStream fis = new FileInputStream(filename);
b=new byte[fis.available()];
fis.read(b);
fis.close();
}
}

为你配合你的思路,我用的byte[]数组读取.