I know how to create DRL files inside KIE workbench by using all the methods. But what my problem is without using the KIE workbench, can we create the .drl fil
The standard tools don't produce DRL files. Instead they encourage you to have templates which are applied to your data at runtime.
You should take a look at the documentation on Decision Tables (specially structured spreadsheets):
http://docs.jboss.org/drools/release/6.0.1.Final/drools-docs/html_single/#d0e4221
... and Rule Templates:
http://docs.jboss.org/drools/release/6.0.1.Final/drools-docs/html_single/#d0e4969