Implementing a CRC check within Android SMS Functionality

I am fairly new to android , but I dont see how it is possible to implement a CRC check, or some kind of message integrity check for a SMS sent from one Android device to another. I'm busy looking at XOR Checksum computations , but I am开发者_如何学JAVA not sure If I am moving in the right direction.

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Use MD5 or some other built-in hash mechanism.

http://exampledepot.com/egs/java.security/Digest.html