android客户端从服务器端下载文件，服务端返回文件流(文件不在项目里)

android客户端从服务器端下载文件，服务端返回文件流

服务端 strtus:

/**

 * 文件下载 ： 返回文件流

 * @param mapping

 * @param actionForm

 * @param request

 * @param response

 * @return

 * @throws Exception

 */

public ActionForward fileUpload(ActionMapping mapping, ActionForm actionForm, HttpServletRequest request, HttpServletResponse response) throws Exception{

logger.debug("fileUpload()");

RequestMap params = WebUtil.getQueryMap(request);

String file_key = (String)params.get("filekey", "");

if(file_key != null && !"".equals(file_key)){

NewsPaperManager service = NewsPaperManager.getInstance();

String file_path = service.getFilePath(file_key);

if(file_path != null && !"".equals(file_path)){

File file = new File(file_path);

if(file.exists()){

InputStream fis = new BufferedInputStream(new FileInputStream(file));

byte[] buffer = new byte[fis.available()];

fis.read(buffer);

fis.close();

// 清空response

response.reset();

// 设置response的Header

response.setHeader("Content-Type", "application/octet-stream");

response.addHeader("Content-Disposition", "attachment;filename="

+ file.getName());

response.addHeader("Content-Length", "" + file.length());

OutputStream toClient = response.getOutputStream();

toClient.write(buffer);

toClient.flush();

toClient.close();

}

}

}

return null;

}

android客户端：

    public byte[] getImage(String path) throws Exception {

URL url = new URL("http://120.197.230.53:9902/kuchuan_api/newspaper.do?method=fileUpload&filekey=2LM7vAcHt8iFX2ABTXZT");

HttpURLConnection conn = (HttpURLConnection)url.openConnection();//基于HTTP协议的连接对象

conn.setConnectTimeout(5000);//请求超时时间 5s

conn.setRequestMethod("GET");//请求方式

Log.i("ResponseCode", "prepare");

Log.i("ResponseCode", conn.getResponseCode()+"");

if(conn.getResponseCode() == 200){//响应码==200 请求成功

InputStream inputStream = conn.getInputStream();//得到输入流

Log.i("ResponseCode", inputStream.toString().length()+"");

ByteArrayOutputStream arrayOutputStream = new ByteArrayOutputStream();

byte[] buffer = new byte[1024];

int len = 0;

Log.i("ResponseCode", "inputStream.read(buffer) :"+inputStream.read(buffer)+"");

while((len = inputStream.read(buffer)) != -1){

arrayOutputStream.write( buffer, 0, len);

Log.i("ResponseCode", "buffer.length :"+buffer.length+"  " + len);

}

inputStream.close();

arrayOutputStream.close();

Log.i("ResponseCode", "arrayOutputStream.toByteArray().length :"+arrayOutputStream.toByteArray().length+"");

}

return null;

}