I'm using Spring 3.1, Jetty, various OWASP, guava. I am in the code of Spring and Jetty on a daily basis, and OWASP when I first used it. I learned guava by wri

I'm using Spring 3.1, Jetty, various OWASP, guava. I am in the code of Spring and Jetty on a daily basis, and OWASP when I first used it. I learned guava by writing unit tests to verify my assumptions - assumptions I learned from the documentation - and which turned out to be wrong in key aspects. Documentation is ambiguous, and even documentation which is unambiguous is often wrong (or perhaps more kindly, "out of date").