The Ternary Conditional Operator ? : in Java

Sadia SherFebruary 25th, 2021Last Updated: January 12th, 2022

2 63 1 minute read

In this article, we will explore the ternary operator ?(question mark) and :(colon) in Java, what is its purpose, and why do we use it?

1. What is a Ternary Operator?

The operator ? : in Java, is a ternary operator. It uses to evaluate a boolean expression. It is also known as a conditional operator. It consists of three operands separated by two operators: question mark (?) and colon(:). Its structure is as below:

z = (boolean expression to evaluate) 
    ? (value assign to 'z' if true) 
    : (value assign to 'z' if false)

In above example, parenthesis are optional.

2. Why we use it?

It is much similar to the if-else statement. However, the goal of the ternary operator is to evaluate the expression and decide which one of the values assign in a variable. Unlike the if-else statement, where a block of code spreads over several lines, it is one line statement.

3. Examples using the ternary operator in Java

public class TernaryOperatorBooleanTest {
	public static void main(String[] args) {		
		int totalMangoes = 6;
            // ternary operator example
		boolean isDozen = totalMangoes == 12 ? true : false;
		System.out.println("Mangoes count is dozen:"+isDozen);
	}
}

In the preceding code, totalMangoes is set as 6, then isDozen value is assigned by evaluating the condition totalMangoes == 12, if the total mangoes are equals to 12 then isDozen is set as true otherwise false.

public class TernaryOperatorStringTest {
	public static void main(String[] args) {
		int month = 6;
    // ternary operator example
		String season = (month >= 4 && month <=10) ? "summer" : "winter";
		System.out.println("month is in season:"+season);
	}
}

In the above example, boolean expression enclosed in parenthesis makes compound expression means both expressions should evaluate to get a final boolean value and set value in season accordingly.

You can also check the Ternary Operator Java Example.