图片下载IO流代码参考

private void sendPicture(HttpServletRequest request,
HttpServletResponse response, File file, String fileName)
throws FileNotFoundException, IOException {

FileInputStream fileInput = new FileInputStream(file);
BufferedInputStream in = new BufferedInputStream(fileInput);

ByteArrayOutputStream bArray = new ByteArrayOutputStream();

byte[] tempByte = new byte[1024];
while (true) {
int tempBL = in.read(tempByte);
if (tempBL == -1) {
break;
}
bArray.write(tempByte, 0, tempBL);
}

response.setContentType("image/gif");

javax.servlet.ServletOutputStream out = response.getOutputStream();
tempByte = bArray.toByteArray();
response.setContentLength(tempByte.length);
out.write(tempByte, 0, tempByte.length);
out.flush();
out.close();
fileInput.close();
in.close();

}