在Android上传大文件，不会出现内存不足错误

我的上传代码如下：

String end = "\r\n"; String twoHyphens = "--"; String boundary = "*****"; try { URL url = new URL(ActionUrl); HttpURLConnection con = (HttpURLConnection) url.openConnection(); con.setDoInput(true); con.setDoOutput(true); con.setUseCaches(false); con.setRequestMethod("POST"); con.setRequestProperty("Connection", "Keep-Alive"); con.setRequestProperty("Accept", "text/*"); con.setRequestProperty("Content-Type", "multipart/form-data; boundary=" + boundary); DataOutputStream ds = new DataOutputStream(con.getOutputStream()); ds.writeBytes(twoHyphens + boundary + end); ds.writeBytes("Content-Disposition: form-data;" + "name=\"folder\"" + end + end); ds.write(SavePath.getBytes("UTF-8")); ds.writeBytes(end); ds.writeBytes(twoHyphens + boundary + end); ds.writeBytes("Content-Disposition: form-data;" + "name=\"Filedata\"; filename=\""); ds.write(FileName.getBytes("UTF-8")); ds.writeBytes("\"" + end); ds.writeBytes(end); FileInputStream fStream = new FileInputStream(uploadFilepath+""+FileName); int bufferSize = 1024; byte[] buffer = new byte[bufferSize]; int length = -1; int pro = 0; while((length = fStream.read(buffer)) != -1) { ds.write(buffer, 0, length); } ds.writeBytes(end); ds.writeBytes(twoHyphens + boundary + twoHyphens + end); fStream.close(); ds.flush(); InputStream is = con.getInputStream(); int ch; StringBuffer b = new StringBuffer(); while((ch = is.read()) != -1) { b.append((char)ch); } ds.close(); } catch(Exception e) { e.printStackTrace(); } 

虽然小于16 MB，但它上传成功。 但是，当它超过16 MB，“OutOfMemory”错误显示。 如何避免outofmemory错误？

Answer 1

你尝试过吗？

 con.setChunkedStreamingMode(1024); 

这将帮助您将数据分块为特定的大小，这样就不需要将整个文件保存在内存中。

更新：

尝试使用下面的方法。 我使用这种方法上传一个80 MB的文件没有例外。

 public String sendFileToServer(String filename, String targetUrl) { String response = "error"; Log.e("Image filename", filename); Log.e("url", targetUrl); HttpURLConnection connection = null; DataOutputStream outputStream = null; // DataInputStream inputStream = null; String pathToOurFile = filename; String urlServer = targetUrl; String lineEnd = "\r\n"; String twoHyphens = "--"; String boundary = "*****"; DateFormat df = new SimpleDateFormat("yyyy_MM_dd_HH:mm:ss"); int bytesRead, bytesAvailable, bufferSize; byte[] buffer; int maxBufferSize = 1 * 1024; try { FileInputStream fileInputStream = new FileInputStream(new File( pathToOurFile)); URL url = new URL(urlServer); connection = (HttpURLConnection) url.openConnection(); // Allow Inputs & Outputs connection.setDoInput(true); connection.setDoOutput(true); connection.setUseCaches(false); connection.setChunkedStreamingMode(1024); // Enable POST method connection.setRequestMethod("POST"); connection.setRequestProperty("Connection", "Keep-Alive"); connection.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary); outputStream = new DataOutputStream(connection.getOutputStream()); outputStream.writeBytes(twoHyphens + boundary + lineEnd); String connstr = null; connstr = "Content-Disposition: form-data; name=\"uploadedfile\";filename=\"" + pathToOurFile + "\"" + lineEnd; Log.i("Connstr", connstr); outputStream.writeBytes(connstr); outputStream.writeBytes(lineEnd); bytesAvailable = fileInputStream.available(); bufferSize = Math.min(bytesAvailable, maxBufferSize); buffer = new byte[bufferSize]; // Read file bytesRead = fileInputStream.read(buffer, 0, bufferSize); Log.e("Image length", bytesAvailable + ""); try { while (bytesRead > 0) { try { outputStream.write(buffer, 0, bufferSize); } catch (OutOfMemoryError e) { e.printStackTrace(); response = "outofmemoryerror"; return response; } bytesAvailable = fileInputStream.available(); bufferSize = Math.min(bytesAvailable, maxBufferSize); bytesRead = fileInputStream.read(buffer, 0, bufferSize); } } catch (Exception e) { e.printStackTrace(); response = "error"; return response; } outputStream.writeBytes(lineEnd); outputStream.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd); // Responses from the server (code and message) int serverResponseCode = connection.getResponseCode(); String serverResponseMessage = connection.getResponseMessage(); Log.i("Server Response Code ", "" + serverResponseCode); Log.i("Server Response Message", serverResponseMessage); if (serverResponseCode == 200) { response = "true"; } String CDate = null; Date serverTime = new Date(connection.getDate()); try { CDate = df.format(serverTime); } catch (Exception e) { e.printStackTrace(); Log.e("Date Exception", e.getMessage() + " Parse Exception"); } Log.i("Server Response Time", CDate + ""); filename = CDate + filename.substring(filename.lastIndexOf("."), filename.length()); Log.i("File Name in Server : ", filename); fileInputStream.close(); outputStream.flush(); outputStream.close(); outputStream = null; } catch (Exception ex) { // Exception handling response = "error"; Log.e("Send file Exception", ex.getMessage() + ""); ex.printStackTrace(); } return response; } 

Answer 2

 bitmap=Bitmap.createScaledBitmap(bitmap, 100, 100, true); ByteArrayOutputStream stream = new ByteArrayOutputStream(); bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream); //compress to format you want. byte [] byte_arr = stream.toByteArray(); String image_str = Base64.encodeBytes(byte_arr); 

我尝试过的最好的方式对我来说是成功的！