"Note that the code always refers to the Collection by its interface type (Set) rather than by its implementation type (HashSet). This is a strongly recommended programming practice because it gives you the flexibility to change implementations merely by changing the constructor."

Let's keep this handy just in case.

int length = String.valueOf(1000).length();

Neat.

On TreeMaps.

"The Key Concept is this: If you're looking to change your version of Java on a Mac, do not change your PATH. Instead, change the CurrentJDK and/or Current alias in the Framework."

"If you have a class name used in more than one package, you will save yourself a lot of grief if you always fully qualify references to it, rather than relying on import. The computer may understand but, your fellow programmers will often be confused by the lack of qualification. Beware of java.util.List and java.awt.List."

/Library/Java/JavaVirtualMachines

"A couple of days ago I encountered this article: How Shazam Works. This got me interested in how a program like Shazam works… And more importantly, how hard is it to program something similar in Java?"