Using Google Phone Utils
Using certs and migrating certs from different version and debugging with keytool.
How to use Java for various projects.
Using numbers in Java can be tricky if you don't know what shadowing is doing with them.
Using hibernate sequence generator to change the behavior of the id generation.
When you don't want your app to fail on redis connections on startup.
How to support null properties, clean up component scan and nullable beans
How to query a database table with an IN statement in JPA.
Using Apache Commons IO for copying streams and loading a file into a String.
Using Apache Commons Lang for simple string templates