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How do you implement a good profanity filter?
I have to take a city name from users as input, but I don't want to accept any profanities. Can anyone tell me how I can keep users from typing such words?
You'd have to scan the input for all vulgarity, either post-entry or during the entry, and reject the content then. Inversoft (http://www.inversoft.com/) has a web service available that can help; you can also do a google search for "java profanity filter" to find other similar products.