java - 使用 FileItemStream 在 Java 中处理二进制文件

Question

我有一个允许上传二进制文件的网络应用程序。我必须解析它们并将内容 1:1 保存到一个字符串中，然后再保存到数据库中。

当我在 unix 机器上使用 uuencode 对二进制文件进行编码时，它就可以工作了。有没有办法在 Java 中自动执行此操作？

if (isMultipart) {

            //Create a new file upload handler
            ServletFileUpload upload = new ServletFileUpload();

            //Parse the request
            FileItemIterator iter = upload.getItemIterator(request);

            while (iter.hasNext()) {
                FileItemStream item = iter.next();
                String name = item.getFieldName();

                InputStream stream = item.openStream();

                if (!item.isFormField()) {

                    BufferedReader reader = new BufferedReader(new InputStreamReader(stream));
                    String line;
                    licenseString = "";

                    while ((line = reader.readLine()) != null) {
                        System.out.println(line);

                        // Generate License File
                        licenseString += line + "\n";
                    }
                }
            }
            session.setAttribute("licenseFile", licenseString);
            System.out.println("adding licensestring to session. ");
        }

它当然适用于所有上传的非二进制文件。我如何扩展它以支持二进制文件？

Answer 1

// save to file
// =======================================
InputStream is = new BufferedInputStream(item.openStream());
BufferedOutputStream output = null;

try {
    output = new BufferedOutputStream(new FileOutputStream("temp.txt", false));
    int data = -1;
    while ((data = is.read()) != -1) {
        output.write(data);
    }
} finally {
    is.close();
    output.close();
}

// read content of file
// =======================================
System.out.println("content of file:");
try {
    FileInputStream fstream = new FileInputStream("temp.txt");

    DataInputStream in = new DataInputStream(fstream);
    BufferedReader br = new BufferedReader(new InputStreamReader(in));
    String line;

    licenseString = "";
    String strLine;
    while ((strLine = br.readLine()) != null)   {
          System.out.println(javax.xml.bind.DatatypeConverter.printBase64Binary(strLine.getBytes()));
          licenseString += javax.xml.bind.DatatypeConverter.printBase64Binary(strLine.getBytes()) + "\n";
    }                                           
} catch (Exception e) {
    System.err.println("Error: " + e.getMessage());
}