Search code examples
javastaticdoublefinalfractions

Java: public static final double can't be set to decimal fraction?

I have a config file which includes some factors I want to use for calculations.

public class Config {

  public static final double factor = 67/300; // ~0,2233...

}

Im accessing the factors like this:

public class Calculate {

  public static calc() {
    ...
    result *= Config.factor;
    ...

When I do that Config.factor equals 0, so my result is 0, too. I don't have that problem if I set the factor to 0.2233, but that wouldn't be as accurate. Why doesn't setting it to 67/300 work?

Solution

  • Try this:

    public static final double factor = 67/300d;

    The problem is that 67 and 300 are integer literals, so the division ends up being an integer, which is 0. The d at the end of the number makes it a double literal, so the result of 67/300d is a double.

    Note that in the previous code the double literal is 300d. You can also use 67d/300 or 67d/300d.