How to check if a integer is not a decimal in Java

In Java, you can use the modulus operator (%) to check if an integer value is not a decimal. The modulus operator returns the remainder of a division operation, and if the remainder is zero, it means that the number is divisible by the divisor without any remainder, that means it's an integer.

Here's an example of how you can use the modulus operator to check if an integer value is not a decimal:

public boolean isInteger(double value) {
    if (value % 1 == 0) {
        return true;
    } else {
        return false;
    }
}

Alternatively, you can use the Math.floor() method, which returns the largest integer that is less than or equal to a given value. If the value passed to Math.floor() is equal to the value passed to it, it means that the value is an integer.

public boolean isInteger(double value) {
    if (value == Math.floor(value)) {
        return true;
    } else {
        return false;
    }
}

You can also use Math.round() method that returns the closest integer to the argument. If the argument passed is already an integer, the same value will be returned.

public boolean isInteger(double value) {
    if (value == Math.round(value)) {
        return true;
    } else {
        return false;
    }
}

Note that the above examples only check if the value is not decimal, but if you want to check the value is decimal or not, you can simply return the negation of the above methods.

public boolean isDecimal(double value) {
    return !isInteger(value);
}

It's important to note that if you want to check if a value is not decimal, this method will work, but if you want to check if a value is decimal, you should use instanceof to check if it's a double or float, or use the Math.floor() method and compare the value passed to it with the value passed.