This post explains how to use classes in Java to build objects and organize your code. Also learn: constructors, static methods, and more!

HashMap vs. Hashtable similarities Both the Hashtable and HashMap implement the Map interface and both share the same set of methods used to add, remove and manipulate elements of a key-value, ...

Using generics results in more robust code and avoids ClassCastExceptions in your Java programs. This in-depth tutorial introduces you to generics and their types and methods.