Question

In my signed applet I have an Image object, Now I want to save this Image at getCodebase() by creating a new file. I use:

File file2=new File(getCodeBase()+"newFile.gif");
file2.createNewFile();
ImageIO.write(myImage, "png", file2);

To create new file then ImageIO to write file at this destination but it gives the following error.

http://192.168.1.119:96/res/applet/newFile.gif
pgraph.sendImageToServer... exceptionThe filename, directory name, or volume label syntax is incorrect
java.io.IOException: The filename, directory name, or volume label syntax is incorrect
    at java.io.WinNTFileSystem.createFileExclusively(Native Method)
    at java.io.File.createNewFile(Unknown Source)

How to save image on the server from a signed applet?

Answer 1

1. If an applet establishes a File object, that File will point to somewhere on the file-system of the end user’s PC. It can never point back to the server.
2. For an applet to save anything on a server, it needs to return the bytes of the resource to a script on the server that does the part of saving the image.
3. If an applet is ‘phoning home’ to its own server to save an image, it does not need to be digitally signed.