Abstract classes and interfaces in Java serve fundamentally different purposes. Learn the differences between these Java language elements and how to use them in your programs.

To further confuse matters, every Java collection class that implements the List interface does have a size() method. Classes including Vector, Stack and ArrayList all have a size method. So to get ...

1. The Java compiler: javac. The javac utility is the most important command-line interface tool you will find in the JDK's bin directory. This is the Java compiler, and whether you use Maven, Gradle, ...