The scope of the snippet is not limited to any particular source, so it should be able to be used with any file. The snippet keys off of the TAB key, so to activate, literally type:
/**[TAB]
Where [TAB] is replaced by pressing the actual tab key. That expands the comment to a full comment block;
/**[TAB]
Becomes:
/**
*^
*/
The cursor is placed at the "^" marker.