How to add / modify @author tag in all java files

Hi everyone,

I am very new to idea and i am having trouble with a small thing, which i will appreciate if anyone can help me with.

I have an old project with lots of src files with @author tag in a different format.

Also there are some files which dont have @author tag.

I want to add the @author tag in a specified format to all files in my project.

Is there a way this can be done..
This would be really helpful if anyone can suggest something on this.

Thanks
Max