Install a JDK 21 (LTS), e.g. Eclipse Temurin from adoptium.net.
Check: java -version in a terminal.
Save Hello.java and run java Hello.java (Java 11+ runs a single file directly).
“`java
public class Hello {
public static void main(String[] args) {
System.out.println(“Hello from Java!”);
}
}
“`
Every Java program starts in a main method inside a class. The file name must match the public class name.
💡 IntelliJ IDEA Community (free) or VS Code with the Java extension pack gives autocomplete and one-click run, a big help while learning.
Code for this course follows standard, current syntax; we test JavaScript and PowerShell scripts before publishing, and R/Java/Rust examples are kept to core language features. Tell us if anything fails on your setup.
