如何中断数据库中的用户操作

I want to interrupt user actions(Ex: When a user is trying to insert values, modify/delete values in database). I want to check if a specific condition is satisfied in another Java application based on this user action(Ex Cond: A free user is not allowed to modify contents). This Java application will be having information about users. If the condition is satisfied then I can allow this user to perform the action, if not he/she must be denied. Is there any way or specific tools for monitoring or interrupting user actions in a database. I want to interrupt user actions(Ex: When a use