in this case your extension useless… if someone likes to use encryption, then it should be as safe as possible…
Encrypting strings in Android: Let’s make better mistakes
If you do a web search for “encrypting Strings in Android”, you’ll find a lot of example code on sites like Stack Overflow, but those examples are wrong. They definitely input a String and output gibberish that looks like encrypted text, but they are subtly insecure and even dangerous. Crypto is tricky: it’s hard to tell that the gibberish that’s being printed is not good crypto, and it’s hard to tell that the code example you picked up from Stack Overflow has serious flaws.