Strange issue in converting Feet and Inches to Centimeter and Vice Versa

Question

public static double convertFeetandInchesToCentimeter(String feet, String inches) {
    double heightInFeet = 0;
    double heightInInches = 0;
    try {
        if (feet != null && feet.trim().length() != 0) {
            heightInFeet = Double.parseDouble(feet);
        }
        if (inches != null && inches.trim().length() != 0) {
            heightInInches = Double.parseDouble(inches);
        }
    } catch (NumberFormatException nfe) {

    }
    return (heightInFeet * 30.48) + (heightInInches * 2.54);
}

Above is the function for converting Feet and Inches to Centimeter.Below is the function for converting Centimeter back to Feet and Inches.

public static String convertCentimeterToHeight(double d) {
    int feetPart = 0;
    int inchesPart = 0;
    if (String.valueOf(d) != null && String.valueOf(d).trim().length() != 0) {
        feetPart = (int) Math.floor((d / 2.54) / 12);
        inchesPart = (int) Math.ceil((d / 2.54) - (feetPart * 12));
    }
    return String.format("%d' %d''", feetPart, inchesPart);
}

I have a problem when i enter normal values like 5 Feet and 6 Inches, its converting perfectly to centimeter and again it gets converted back to 5 Feet and 6 Inches.

The Problem is when i convert 1 Feet and 1 inches or 2 Feet and 2 inches, its getting converted back to 1 Feet 2 inches and 2 Feet 3 inches.

Answer 1

I ran the following code

public class FeetInches{

    public static void main(String[] args){

        double d = convertFeetandInchesToCentimeter("1","1");

        String back_again = convertCentimeterToHeight(d);

        System.out.println(back_again);


    }

    public static double convertFeetandInchesToCentimeter(String feet, String inches) {
        double heightInFeet = 0;
        double heightInInches = 0;
        try {
        if (feet != null && feet.trim().length() != 0) {
            heightInFeet = Double.parseDouble(feet);
        }
        if (inches != null && inches.trim().length() != 0) {
            heightInInches = Double.parseDouble(inches);
        }
        } catch (NumberFormatException nfe) {

        }
        return (heightInFeet * 30.48) + (heightInInches * 2.54);
    }


    public static String convertCentimeterToHeight(double d) {
        int feetPart = 0;
        int inchesPart = 0;
        if (String.valueOf(d) != null && String.valueOf(d).trim().length() != 0) {
        feetPart = (int) Math.floor((d / 2.54) / 12);
        System.out.println((d / 2.54) - (feetPart * 12));
        inchesPart = (int) Math.ceil((d / 2.54) - (feetPart * 12));
        }
        return String.format("%d' %d''", feetPart, inchesPart);
    }


}

And got

1.0000000000000018
1' 2''

By using the ceiling function you are rounding up to 2 when you really want to be rounding down to 1.