Java program to check if a number is positive or negative

Java Comprehensive Examples

In this program, you will learn how to check if a given number is positive or negative. This is done by using if else statements in Java.

Example: Use if else to check if a number is positive or negative

public　class　PositiveNegative　{
　　　　public　static　void　main(String[]　args)　{
　　　　　　　　double　number　=　12.3;
　　　　　　　　//If number is less than 0, it is true
　　　　　　　　if　(number　<　0.0)
　　　　　　　　　　　　System.out.println(number　+　"　is a negative number.");
　　　　　　　　//If number is greater than 0, return true
　　　　　　　　else　if　(　number　>　0.0)
　　　　　　　　　　　　System.out.println(number　+　"　is a positive number.");
　　　　　　　　//　If both test expressions are calculated as false
　　　　　　　　else
　　　　　　　　　　　　System.out.println(number　+　"　is　0.");
　　　　}
}

When running the program, the output is:

12.3　It is a positive number.

If the value is changed to a negative number (for example-12.3），then the output is:

-12.3　It is a negative number.

In the above program, by comparing the variable number with 0, it can be clearly seen whether the variable number is positive or negative.

If unsure, please follow the following steps:

• If the number is greater than zero, it is a positive number.

• If the number is less than zero, it is a negative number.

• If the number is zero, it is zero.

Java Comprehensive Examples