是否可以在Java中将.swf文件转换为base64格式

Question

I am trying to load a .swf file in my page, i would like to make this load faster by converting it to Base64, rather providing a src. This is working great with image formats by using the below code

Java code

BufferedImage buffImg = ImageIO.read(new File(imagePath));
ImageIO.write(buffImg, imgExtension, bos);
byte[] imageBytes = bos.toByteArray();                  
BASE64Encoder encoder = new BASE64Encoder();    
imageString = encoder.encode(imageBytes);

but this is not working for swf file. is there any possible way to achieve this.

Html

<object width="10" height="10" data="data:application/x-shockwave-flash;base64, RldTCSEAAABIAZAAZAAADAEARBEIAAAAQwIAAP9AAAAA"></object>

thanks in advance.

Answer 1

Trying to get the file in base64 will not speed up the file transfer, it's just the opposite as it will convert the file which is stored in bytes (base256 if it can be said that way) to base64 (64 printable characters), so the final amount of data you will be transfering is more.

The only "win" is that you might be able to load it as part of the page instead of the browser making another call for the swf file, which should be no issue on http 1.1.

Unless you have some other good reason to do this, I would not suggest this kind of practice.

If you have your swf file(s) in a database as a blob, you could just make a servlet which sets the proper contenttype and write the whole file with the ServletOutputStream, without any tags. In your html code, you would have to reference to the servlet instead of a fixed file.

If you still want to convert the file to base64, you shouldn't use some image API, but get the file in a standard way for binary files, here's a sample that should do the job:

http://www.javapractices.com/topic/TopicAction.do?Id=245

You can still do the encoding as you did it once you have a byte array:

File file = new File(imagePath);
log("File size: " + file.length());
byte[] result = null;
try {
  InputStream input =  new BufferedInputStream(new FileInputStream(file));
  result = readAndClose(input);
}
catch (FileNotFoundException ex){
  log(ex);
}
BASE64Encoder encoder = new BASE64Encoder();    
imageString = encoder.encode(result);

And the readAndClose method:

byte[] readAndClose(InputStream aInput){
  byte[] bucket = new byte[32*1024]; 
  ByteArrayOutputStream result = null; 
  try  {
    try {
      result = new ByteArrayOutputStream(bucket.length);
      int bytesRead = 0;
      while(bytesRead != -1){
        bytesRead = aInput.read(bucket);
        if(bytesRead > 0){
          result.write(bucket, 0, bytesRead);
        }
      }
    }
    finally {
      aInput.close();
    }
  }
  catch (IOException ex){
    log(ex);
  }
  return result.toByteArray();
}

This should do the trick, maybe some fine tunings to adapt the code to your specific situation, optimize it and better error handling...