my another question is when i install spark messenger then i need to startup logo is flashed spark there i need to use my company logo. is it possible for me or possible for only software developers
If you just need to change image on the login screen, then you can open Spark\lib\spark.jar with an archiver (on Windows i use 7-zip for this), go to src\resources\images folder and replace spark.gif with your own image, then archive that file again and check how it works. Then you can copy your customized spark.jar to other clients. If you want to have it in your own installer, then i can’t help you.