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.

Java arrays - a brief tutorial 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.

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.

How to Assign Random Numbers to an Array in Java. Java has a "Random" class that lets you generate a random number you use to implement calculations in your Java source code.

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 ...

The need to find the length of a Java String is a common programming requirement. Learn how to get the size of a Java String and avoid lengthy errors developers often encounter.