Here's how to make classes, fields, methods, constructors, and objects work together in your Java programs.

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.

Describe the bug I tried customized QuarkusMain method as shown in https://quarkus.io/guides/lifecycle#the-main-method with Java 21 Instance Main Methods (preview feature).

Say goodbye to the public static void main method in Java 21 with the unnamed classes and instance main methods preview features.

You don’t need to compile your Java code. Java programs will run without a main method. Semicolons can be optional. Hundreds of extra classes are imported automatically. Exception handling is optional ...

If your main method throws an exception, e.g. @SpringBootApplication public class DemoApplication { public static void main (String [] args) { SpringApplication.run (DemoApplication.class, args); ...