Getting unexpected results when type casting between long and double

Question

I have this code

public class LimitTest{
    public static void main(String[] args){
        long l;
        double d;
        l = 9223372036854775807L;// The largest number a long can hold.
        d = l;
        System.out.println(l);
        System.out.println(d);
        System.out.println(l == d);
    }
}

Now, the result it produces is kinda unexpected, but again, I am not very experienced with type conversions.

Output

9223372036854775807
9.223372036854776E18
true

Now, the two numbers printed are clearly NOT EQUAL, so why does l == d return true?

Answer 1

The variables l and d have different types, so the expression long == double casts the long to a double ...

P.S. l is a bad variable name imho, since it looks a lot like 1 when glancing over code.