Java Development Tools

Hi Everyone,
I am currently using Oracle JDeveloper 11g R2 to develop an application. One of the main problems I have had is how to implement security at a block/table level. For Example, In oracle forms, if a user doest have insert privileges on a table based on certain conditions, I will simply call set_block_property and disable inserting. This way I could use one form and assign it to many people but programmatically control insert, update and delete to a table through the block. In ADF however, I have the option of ADF Table or ADF read only table. My questions are;

1. How can I change the ADF table to Read Only and Insert Enabled at runtime using code (java)? e.g if user = jane then insert yes else insert no
2. Is there a better solution to my problem?

Thanks.

Eric