Bruce: cryptography in Java made easy
Bruce is a Java library that simplifies cryptography operations, making it easy for developers to implement secure encryption, decryption, and hashing in their applications.

I just released Bruce, a Java library for performing cryptography.
Here are the relevant links:
There still is much room for improvement.
If you are new to open source Java library development, a good place to start is taking a look at the open issues. Most of them are pretty easy.
I hope you find this useful. I certainly have in my daily work.