Java - Float Class isNaN() Method

Float class isNaN() method: Here, we are going to learn about the isNaN() method of Float class with its syntax and example. By Preeti Jain Last updated : March 21, 2024

Syntax

public boolean isNaN ();
public static boolean isNaN(float value);

Float class isNaN() method

isNaN() method is available in java.lang package.
isNaN() method is used to check NaN values (i.e. either positive NaN or negative NaN).
isNaN(float value) method is used to check NaN values for the given float argument (i.e. either positive or negative NaN).
isNaN() method does not throw an exception at the time of checking NaN values represented by the object.
Similarly, the isNaN(float value) method does not throw an exception at the time of checking NaN values of the given argument.
They are non-static methods, they are accessible with the class object only and if we try to access the method with the class name then we will get an error.

Parameters

In the first case isNaN(), we don't pass any parameter or value.
In the second case isNaN(float value), we pass only one parameter of the float type it represents the float value to be tested for NaN.

Return Value

In the first case, the return type of this method is boolean, it returns a boolean value either true or false depending on the following cases,

If the value represented by the object is either positive NaN or negative NaN, it returns true.
Else, if the value represented by the object is not either positive NaN or negative NaN, it returns false.

In the second case, The return type of this method is boolean, it returns boolean value either true or false depending on the following case,

If the given argument value is either positive NaN or negative NaN, it returns true.
Else, if the given argument value is not either positive NaN or negative NaN, it returns false.

Example

// Java program to demonstrate the example 
// of isNaN() method of Float class

public class IsNaNOfFloatClass {
    public static void main(String[] args) {
        // Object initialization
        Float ob1 = new Float(0.0 / 0.0);
        Float ob2 = new Float(-0.0 / 0.0);
        Float ob3 = new Float(20.0);

        // Display ob1,ob2 and ob3 values
        System.out.println("ob1 :" + ob1);
        System.out.println("ob2: " + ob2);
        System.out.println("ob3: " + ob3);

        // It checks NaN by calling ob1.isNaN() for ob1
        // and ob2.isNaN() for ob2  
        boolean NaN1 = ob1.isNaN();
        boolean NaN2 = ob2.isNaN();

        // It also checks for NaN of this Float object by calling
        // Float.isNaN(ob3) for ob3 
        boolean NOTNaN = ob3.isNaN(ob3);

        // Display result values
        System.out.println("ob1.isNaN(): " + NaN1);
        System.out.println("ob2.isNaN(): " + NaN2);
        System.out.println("Float.isNaN(ob3): " + NOTNaN);
    }
}

Output

ob1 :NaN
ob2: NaN
ob3: 20.0
ob1.isNaN(): true
ob2.isNaN(): true
Float.isNaN(ob3): false

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