在文件中写入byte []对象并将文件发送到服务器

时间:2015-04-30 13:15:44

标签: java android

我试图在android客户端上的文件中写一个byte [](加密文本),然后将此文件发送到服务器(使用HTTP)。该文件在移动设备中正确创建,但当它存储在服务器端时,它会创建一个0字节的文件。

这里是编写文件的android代码

    File file = new File(getExternalCacheDir(), "index.txt");
    FileOutputStream fout = new FileOutputStream(file);
    ObjectOutputStream oos = new ObjectOutputStream(fout);
    oos.writeObject(encIndex);
    oos.close();

这是用于读取和存储文件的servlet代码

    String fileName = request.getHeader("fileName");
    File saveFile = new File(SAVE_DIR + fileName);
    // opens input stream of the request for reading data
    InputStream inputStream = request.getInputStream();

    // opens an output stream for writing file
    FileOutputStream outputStream = new FileOutputStream(saveFile);

    byte[] buffer = new byte[BUFFER_SIZE];
    int bytesRead;
    System.out.println("Receiving data...");

    while ((bytesRead = inputStream.read(buffer)) != -1) {
        outputStream.write(buffer, 0, bytesRead);
    }

    System.out.println("Data received.");
    outputStream.close();
    inputStream.close();

    System.out.println("File written to: " + saveFile.getAbsolutePath());

    file.close();

客户端到服务器文件发送的代码

    File uploadFile = new File(filePath, fileName);
    URL url = new URL(UPLOAD_URL);
    HttpURLConnection httpConn = (HttpURLConnection)url.openConnection();
    httpConn.setUseCaches(false);
    httpConn.setDoOutput(true);
    httpConn.setRequestMethod("POST");
    httpConn.setRequestProperty("fileName", uploadFile.getName());

    OutputStream outputStream = httpConn.getOutputStream();
    FileInputStream inputStream = new FileInputStream(uploadFile);
    byte[] buffer = new byte[BUFFER_SIZE];
    int bytesRead;
    while ((bytesRead = inputStream.read(buffer)) != -1) {
        outputStream.write(buffer, 0, bytesRead);
    }
    outputStream.close();
    inputStream.close();

由于某些原因,我无法使用Socket。 android没有显示任何错误。服务器显示的错误是,文件为空/我在空文件

上操作

2 个答案:

答案 0 :(得分:0)

fout.write(encIndex);
fout.close();

或者

BufferedOutputStream oos = new BufferedOutputStream(fout,
    Math.min(4086, encIndex.length));
oos.write(encIndex);
oos.close();

答案 1 :(得分:0)

问题在于,我发送了更多带URL的数据,即https://ip:8084/project/servelt?reqid=something&data=something

代码,不知何故,不允许我先读取参数,我需要先读取文件,然后再从URL中读取参数......

Jean和Joop,谢谢你的建议。