Java Programming

Hi,
In my project, we are using java.util.logging. All classes are loading logger at the server start up. These all are intializing through configuration file.
Now i want to change level of log on request basis. Means there is a page where changing log level requested. On this request i need to set the log level to requested level.
To do this i have tried to use below methods. But nothing working.
- Changing log level in configuration file and calling LogManage.readConfigruation()
- Changing log level to package using logManager
- changing log level thru handlers.

In above first method is not at all working.
Second method, showing changing level at only that class but not in any other classes.
Please advise me how to do this? Thanks for your help.