How to use the JOptionPane’s showOptionDialog method Java’s JOptionPane provides a simple way to read input from the user and display information back. The JOptionPane’s list of methods includes many ...

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.

Right-click the Java file you want to edit and select "Open With." Click your Java compiler to open the code in the editor. Add the "Random" class library to the top of the source code file.

In Java, some array types are covariant and/or contravariant. In the case of covariance, this means that if T is compatible to U, then T[] is also compatible to U[].

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.