The **`isNaN` method** of the `Float` class is used to check if the specified `Float` number is a `NaN` (Not-a-Number) value.

#    
## Syntax

There are two methods available to check if the float value is `NaN`.

1. The first is a static method, which takes a float value as an argument.

```java
public static boolean isNaN(float val)
```
2. The second method checks if the value of the current object is `NaN`.

```java
public boolean isNaN()
```
## Parameters
- `val`: the `Float` object passed to the first definition of the function.
- The second definition does not take any parameters as it is called on the specified object itself.
## Return value
This method returns `true` if the value is `NaN`. Otherwise, it returns `false`.

## Code

The code below uses the `isNaN` method.

class FloatIsNaN {

    public static void main(String args[])
    {
        Float val1 = Float.NaN;
        Float val2 = 1.0f;
        
        System.out.println(val1 +" - " + val1.isNaN()); // definition 2
        System.out.println(val1 +" - " + Float.isNaN(val1)); // defiinition 1
        System.out.println(val2 +" - " + Float.isNaN(val2));
    }
}

## Explanation

In the code above: 

* In line 5, we created a `Float` object with the name `val1` and values `NaN`.

* In line 6, we created another `Float` object with the name `val12` and values `1.0f`. 

* In line 8, we checked if the value of the object `val1` is `NaN` using the class method `isNaN` of the `Float` class. We will get `true` as a result.

* In line 9, we checked if the value of the object `val1` is `NaN` using the static method `isNaN` of the `Float` class. We will get `true` as a result.

* In line 10, we checked if the value of the object `val2` is `NaN` using the static method `isNaN` of the `Float` class. We will get `false` as a result.

What is Float.isNaN() in Java?

Float's isNaN() method checks if a specified float value or object's value is NaN, returning true if it is.