Subtraction Operator Example in Java

Introduction

Subtraction Operator is a classic Java console program that demonstrates the concept with complete source code and sample output. Operators combine values, compare results and update variables — core skills for every Java program.

This tutorial walks through the program line by line, explains how the logic works, and highlights best practices you can apply in your own code.

Definition

Operators in Java are similar to those in C++. However, there is no delete operator due to garbage collection mechanisms in Java, and there are no operations on pointers since Java does not support them. Subtraction operator is an unary minus operator.

Syntax

data_type variable_name1= variable_name2 - variable_name3;

Subtraction Operator Example Program

class SubtractionOperator{
	public static void main(String[] args){
		int num1,num2,result;
		num1=12;
		num2=8;
		System.out.println("num1=12; num2=8");
		result=num1-num2;
		System.out.println("The result after subtraction of these numbers is : "+result);
	}
}

Sample Output

Output is 
num1=12; num2=8
The result after subtraction of these numbers is : 4

When to use

Use this subtraction operator example when learning or revising core Java syntax.

How it works

1. Execution begins in the main method — the JVM calls this method when you run the class.

2. num1=12; updates a variable used in the calculation or output.

3. num2=8; updates a variable used in the calculation or output.

4. A println / print call writes text to the console — part of the sample output below.

5. result=num1-num2; updates a variable used in the calculation or output.

6. A println / print call writes text to the console — part of the sample output below.

7. Compare your console output with the sample output for Subtraction Operator to confirm the program behaves correctly.

Best Practices

• Use meaningful variable and class names that describe their purpose.
• Compile and run the program locally — modify values to see how output changes.
• Read compiler errors carefully; they usually point to the exact line to fix.

Common Mistakes

• Copying code without understanding each line — practice by changing one statement at a time.
• Mismatching the public class name and the .java filename.
• Forgetting semicolons at the end of statements.