[java] Checking if a number is an Integer in Java

    double x == 2.15;

    if(Math.floor(x) == x){
        System.out.println("an integer");
    } else{
        System.out.println("not an integer");
    }

I think you can similarly use the Math.ceil() method to verify whether x is an integer or not. This works because Math.ceil or Math.floor rounds up x to the nearest integer (say y) and if x==y then our original `x' was an integer.