Introduction to Java

Source: Dev.to

How does Java code written by humans get executed by machines?

It uses a translation system (JDK → JRE → JVM → JIT) to convert the programming language to machine language.

What is JDK?

• JDK stands for Java Development Kit.
• Java source files should be saved with the .java extension (e.g., Sample.java).
• If there are no errors, the .java file is compiled into a .class file (e.g., Sample.class).
• The .java file is human‑readable, while the .class file is not directly readable.
• If there are errors, the compiler reports them with specific details such as the line number (e.g., line 3).