I have created a sketch to read MD2 Quake models files and display them. It works fine in Processing but when exported to an applet and uploaded to a website the createInput() method throws an exception. The following code opens a file stream

Any suggestions or solutions greatly appreciated.

Thanks
.
Code:

  private boolean openBuffer(String mdlFile){
    try {
	fin = (FileInputStream)app.createInput(mdlFile);
    } 
    catch (Exception ex){
	System.out.println("Can't create file stream");
	return false;
    }
    try{
	fc = fin.getChannel();
    } 
    catch(Exception ex) {
	System.out.println("Can't create channnel");
	return false;
    }
     if(fin == null){
	System.out.println("File Channel is NULL");
	return false;
    }
    try{
	buf = ByteBuffer.allocateDirect((int)fc.size());
	if(buf == null){
	  System.out.println("failed to allocate buffer buf = null");
	}
	fc.read(buf);
	// BIG_ENDIAN is the default - might be for Java
	// but the file was created with a C++ program
	buf.order(ByteOrder.LITTLE_ENDIAN);
	buf.rewind();
    }
    catch(Exception ex) {
	System.out.println("Can't allocate buffer");
	return false;
    }
    return true;
  }
 

The problem is that createInput() returns a FileInputStream when run inside Processing and I assumed that it did the same when run as an applet in a web browser - I was wrong (my thanks to Fry for pointing out the error).

I did some experiments and found that createInput() returns a ZipFile object because the file is now being read from the sketch.jar file.

Since an MD2 file is a binary file and is normally read using C++ it requires unsigned integral types (i.e. unsigned short, unsigned int etc) which Java hasn't got. I got round the problem by using a ByteBuffer reading the appropriate number of bytes and when required performing the conversion from C++ primitive to Java primitive types and this (ByteBuffer) works well with FileInputStream but not ZipFile.

Anyway I have got to the point were I can read the entries in a jar file and the next stage is to read the entries I need into a ByteBuffer, thus removing the need for a FileInputStream

When it is complete I will make it available in the Exhibition forum