Matching that decryption is very easy in Java using the JCE ( http://docs.oracle.com/javase/1.5.0/docs/guide/security/CryptoSpec.html ) . If you have worked with cryptography before then you will find the specification enough but if not then you would do well to buy a book. A good introduction is given in "Beginning Cryptography with Java" written by David Hook published by Wrox.
Note - for the work you are doing PKCS7 padding is equivalent to PKCS5 padding and you should specify PKCS5Padding when creating the Cipher object.
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