I've been given a task to make some conversions from ft and in to cm. I've gotten most of this down and the conversions do work. I also want to include the statement of A negative number...
or A non-digit...
when I type a string, for example, or a negative number, to display said message.
The problem I am getting is that when I do type up a string or negative number, I get the output of testProgram.NegativeNumberException
when I enter -9
, for example. And testProgram.NonDigitNumberException
, when I enter joe
, for example.
I am thinking there is something wrong in the catch
but not sure exactly where it won't click.
package testProgram;
import java.util.InputMismatchException;
import java.util.Scanner;
public class conversion{
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
double cm = -1;
while(cm == -1){
cm = convertToCentimeters(scan);
if(cm!=-1){
System.out.println("Your result = " +cm);
}
else{
System.out.println("Please enter the values again.");
}
scan.nextLine();
}
}
public static double convertToCentimeters(Scanner scan){
double centimeters = -1;
try{
double foot = getFootValue(scan);
double inch = getInchValue(scan);
double totalInches = foot * 12 + inch;
centimeters = totalInches * 2.54;
}catch(NegativeNumberException e1){
System.out.println(e1);
}
catch(NonDigitNumberException e2){
System.out.println(e2);
}
return centimeters;
}
public static double getFootValue(Scanner scan) throws NegativeNumberException, NonDigitNumberException{
try{
System.out.println("Enter the foot value: ");
double foot = scan.nextDouble();
if(foot <= 0){
throw new NegativeNumberException ("A negative foot value has been entered.");
}
return foot;
}
catch(InputMismatchException e){
throw new NonDigitNumberException ("A non-digit foot value has been entered.");
}
}
public static double getInchValue(Scanner scan)throws NegativeNumberException, NonDigitNumberException{
try{
System.out.println("Enter the inch value: ");
double inch = scan.nextDouble();
if(inch <= 0){
throw new NegativeNumberException ("A negative inch value has been entered.");
}
return inch;
}
catch(InputMismatchException e){
throw new NonDigitNumberException ("A non-digit inch value has been entered.");
}
}
}
Alternatively to @Scary's suggestion, you can add a constructor to your custom exceptions as -
NegativeNumberException(String str) {
System.out.println(str);
}
This shall help you print the message when you
throw new NegativeNumberException ("A n....");