上传于Android的大文件，而不内存不足错误 [英] Upload large file in Android without outofmemory error

问题描述

我的上传code如下：

My upload code as below:

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，上传成功。 但是，尽管超过16 MB的内存不足的错误显示。 如何避免内存不足错误？

While smaller than 16 mb, it upload success. But while it more than 16 mb, the "OutOfMemory" error show. How to avoid the outofmemory error?

推荐答案

你有没有尝试使用

con.setChunkedStreamingMode(1024);

这将帮助您大块的数据转换成特定的大小，让你不必让你的整个文件在内存中。

This will help you to chunk your data into specific size, so that you need not keep your entire file in the memory.

更新：

请尝试使用下面的方法。我用这个方法上载80 MB的文件，没有例外。

Try using the below method. I use this method to upload a 80 mb file without Exception.

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;
}

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