can anyone please tell me how to edit the summary of a file(e.g *.txt,*.docs,*.pdf,*.avi.....etc) through by java programming.

What do you mean "the summary of a file"?

file summary is shown in picture............
actually i want to edit that using java programming..........
sir is it possible to do that

You need to be on the .latest version of Java (Java 7, or version 1.7) then you can use the "new I/O" classes to access that kind of metadata.
It's all very new, so there's not a lot of examples on the web yet, but here's a good place to start:
http://download.oracle.com/javase/tutorial/essential/io/fileAttr.html

thanks sir....

one mre thing......

is it possible to hide something in the summary of a file such that the hidden datas written within the summary should not be seen............