Decrement Operator Example in Java

Introduction

Decrement 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 are used to manipulate primitive data types. Java operators can be classified as unary, binary, or ternary?meaning taking one, two, or three arguments, respectively. Decrement operator helps to subtract 1 from a variable.

Syntax

Variable_name--;

Decrement Operator Example Program

class DecrementOperatorDemo{
	public static void main(String args[]){
	int i = 5, j = 5, sum = 0;
	System.out.println("Value of i is " + i + ", j is " + j+ " and sum is " + sum);
	sum = i + j--;
	System.out.println("Value of i is " + i + ", j is " + j +" and sum is " + sum);
	}
}

Sample Output

Value of i is 5, j is 5 and sum is 0
Value of i is 5, j is 4 and sum is 10

When to use

Use this decrement 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. int i = 5, j = 5, sum = 0; updates a variable used in the calculation or output.

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

4. sum = i + j--; updates a variable used in the calculation or output.

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

6. Compare your console output with the sample output for Decrement 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.