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.

This Java runtime exception happens when the wrong type of object is placed into an array. In the example below, a BigInteger array is created, followed by an attempt to add a Double. The Double does ...

In Java an array is a way of storing multiple items of the same type. In this quick tutorial we introduce you to the very basics.

Covariance and contravariance might seem esoteric, but you'll need these concepts more than ever as the Java language evolves. Get started with type dependency in array types, generic types, and ...

For new Java programmers, the JOptionPane class is a great visual and user-friendly introduction to user input and Swing-based programming. Here's how to get started.