Compact source files and instance main

Definition

Compact source files (Java 25) let a small program be just a void main() method, with no class declaration and no public static. It removes the ceremony from a first program or a script.

Example code

A whole program with no class around it

// file: Demo.java  (no class, no "public static", no String[] args)
void main() {
    String name = "Java 25";
    System.out.println("Hello from " + name);
}

// Output:
// Hello from Java 25