Re-learning Java a decade later

Java is the programming language that I have known and used the longest. I learned Java as part of the curriculum when I was in my first year of undergraduate study. Although reluctant at first, I can still recall the joy I felt switching over from C++. No more garbage collection! That was ten years ago. I haven't done any real programming in the last few years as my engineering work has become higher and higher level. Although I have maintained my hobby in developing automated trading strategies and quantitative analysis, much of that work are mere child's play compared to what I have done and much forgotten. Lately, words such as "code smell", "design pattern", and the likes are creeping back into my world as I am comitting myself to pursuit my esoteric fascination in financial engineering. The first step, research, was a few months of testing the possibilities to decide what I should use. Different markets, different brokers, different platforms, and different technology. I decided to study the foreign exchange market through Dukascopy's JForex platform using Java. Although ideally, I would be using Oanda and Python... But I'm not prepared to cough out \$600 per month for Oanda's API. Some of the other tools that I use are RapidMiner and Weka. Both of which offer a Java API. Having learned JForex and programmed a few strategies already, I have tested the water enough. For the past few weeks, I have been taking steps to move to the next level of my development. However, as I play with programming more and more, I realize that I am fundamentally outdated in my programming skills. There were no interface when I learned Java. Neither was there hashset and annotation. As such, before doing anything else, I am just going to pause for the next two weeks while I am travelling in Hong Kong and catch up on my Java knowledge (I just realized that they don't publish those Teach Yourself \<insert topic> in 24 Hours book anymore. The Head First series seem to be the craze nowadays). My goal is to devour a Java book in the 15-hour flight. Let's see if I still got it after ten years.