See the Java 101 Java interfaces tutorial for a more in-depth introduction to using interfaces in your Java programs, including where and where not to use default, static, and private methods.

We discuss how to work with directories, sub-directories, and traverse them using Java and the DirectoryStream method. Learn more.

Learn how to use synchronous and asynchronous callbacks in Java—including callbacks with lambda expressions, CompletableFuture, and more.

How to write a Java palindrome program for Strings Good programmers need to create code that efficiently solves problems, using various methods. A popular academic exercise is to create a program that ...

A method might accept a specific type and its subclasses, but you want to restrict usage to a select few implementations of your own design. Java's open inheritance model can feel like an open ...