Java Programmer Skills Programme

📘LESSON 8

3.1 Lesson Outcomes

After completing this lesson, learners will be able to:

Identify Java source files.
Explain Java syntax rules.
Write basic Java program structures.
Identify important syntax elements in Java.
Explain the importance of proper Java syntax.

3.2 Overview

Java programs are written inside Java source files using specific syntax rules and structures. Java syntax defines how programs must be written so that they can compile and execute correctly.

This lesson introduces learners to Java files and syntax and explains the rules used to structure Java programs correctly.

Java syntax is important in:

software development,
enterprise applications,
Android development,
web applications,
and programming environments.

Understanding Java syntax is important because syntax errors prevent Java programs from compiling and running successfully.

KT0801 — Java Files

Java source code is stored inside files with the:

.java

extension.

Each Java file normally contains:

classes,
methods,
variables,
and program logic.

Example Java File

Main.java

Structure of a Java File

Component	Purpose
Package Statement	Organizes classes
Import Statement	Imports libraries
Class Declaration	Defines program class
Methods	Performs tasks

Example Java File

public class Main {

    public static void main(String[] args) {

        System.out.println("Hello World");
    }
}

Importance of Java Files

Java files help developers:

organize source code,
manage applications,
and structure programs correctly.

KT0802 — Java Syntax

Java syntax refers to the rules used when writing Java programs.

Programs must follow proper syntax to:

compile successfully,
execute correctly,
and remain readable.

Basic Java Syntax Rules

Rule	Description
Statements end with semicolons	`;` terminates statements
Code blocks use braces	`{}` defines blocks
Java is case-sensitive	Uppercase/lowercase matter
Classes use class keyword	Defines classes

Example of Java Syntax

public class Main {

    public static void main(String[] args) {

        int number = 10;

        System.out.println(number);
    }
}

Important Syntax Elements

Element	Purpose
class	Defines a class
main()	Entry point
System.out.println()	Displays output
;	Ends statements
{}	Defines code blocks

Java Comments

Comments are notes written inside programs for explanation purposes.

Single-Line Comment

// This is a comment

Multi-Line Comment

/*
This is
a multi-line comment
*/

Importance of Java Syntax

Proper syntax supports:

successful compilation,
readable code,
easier debugging,
and software quality.

3.5 Key Notes / Summary

Java source files use the .java extension.
Java programs follow specific syntax rules.
Java is case-sensitive.
Statements end with semicolons.
Braces define code blocks.
Comments improve readability and documenta