Do you need to know how to sort Java objects in a collection, array, or map? Here's how to use the Comparable and Comparator interfaces and avoid ClassCastExceptions.

The Java Platform provides the most commonly used data structures in the form of the Collections Framework, and it provides a rich API to operate on them. This article explains the concepts behind ...

Need to add multiple values to a key in a Java HashMap but can't figure out how to do it? Here are three examples of how to solve the multiple values per key problem in Java.