Need to reprompt a statement, but my code continues to the next statement,

Question

In the while statement, after you type a wrong direction i get an error but then procedes to the next question. How can i format it to reprompt for a valid direction? don't know if i should use do while or not to me this seems like the correct approach to take but it doesn't seem to work

import javax.swing.JOptionPane;
public class taxiService {

public static void main(String [] args) {

//Declare constants
double fareCharge = 5;
double totalMiles = 0;
double finalFareCharged = 0;
double finalxCoord = 0;
double finalyCoord = 0;
double numOfMiles = 0;
double finalCoord = 0;
String error = "Invalid data, please enter valid data!";

String directions = "";
boolean reprompt = true;
//Prompt for direction and miles

while (reprompt) {
   totalMiles = numOfMiles + numOfMiles;
   directions = JOptionPane.showInputDialog(null, "Please enter a direction: ");
   if (directions.equalsIgnoreCase("East")) {
      finalxCoord = finalxCoord + numOfMiles;
      reprompt = false;
      }
      else if (directions.equalsIgnoreCase("West")) {
               finalxCoord = finalxCoord - numOfMiles;
               reprompt = false;
               }
             else if (directions.equalsIgnoreCase("North")) {
                     finalyCoord = finalyCoord + numOfMiles;
                     reprompt = false;
                     }
                     else if (directions.equalsIgnoreCase("South")) {
                             finalyCoord = finalyCoord - numOfMiles;
                             reprompt = false;
                             }
             else {
                 reprompt = true;
                 JOptionPane.showMessageDialog(null, error);

        }
   numOfMiles = Double.parseDouble(JOptionPane.showInputDialog(null, "Please enter distance in miles: "));
   if (numOfMiles > 0) {
   JOptionPane.showMessageDialog(null, "miles: " + totalMiles);
   }
   else 
   JOptionPane.showMessageDialog(null, error);


   }
}
}

Kaamil Jasani · Accepted Answer · 2015-10-08T01:11:03.167

Move the second question outside the loop. I think this is what you originally had in mind but made a logic error by putting the second question in the loop.

import javax.swing.JOptionPane;
public class taxiService {

public static void main(String [] args) {

//Declare constants
double fareCharge = 5;
double totalMiles = 0;
double finalFareCharged = 0;
double finalxCoord = 0;
double finalyCoord = 0;
double numOfMiles = 0;
double finalCoord = 0;
String error = "Invalid data, please enter valid data!";

String directions = "";
boolean reprompt = true;
//Prompt for direction and miles

while (reprompt) {
   totalMiles = numOfMiles + numOfMiles;
   directions = JOptionPane.showInputDialog(null, "Please enter a direction: ");
   if (directions.equalsIgnoreCase("East")) {
      finalxCoord = finalxCoord + numOfMiles;
      reprompt = false;
      }
      else if (directions.equalsIgnoreCase("West")) {
               finalxCoord = finalxCoord - numOfMiles;
               reprompt = false;
               }
             else if (directions.equalsIgnoreCase("North")) {
                     finalyCoord = finalyCoord + numOfMiles;
                     reprompt = false;
                     }
                     else if (directions.equalsIgnoreCase("South")) {
                             finalyCoord = finalyCoord - numOfMiles;
                             reprompt = false;
                             }
             else {
                 reprompt = true;
                 JOptionPane.showMessageDialog(null, error);

        }
   }
   numOfMiles = Double.parseDouble(JOptionPane.showInputDialog(null, "Please enter distance in miles: "));
   if (numOfMiles > 0) {
   JOptionPane.showMessageDialog(null, "miles: " + totalMiles);
   }else {
   JOptionPane.showMessageDialog(null, error);


   }
}
}

OR

Add continue; after showing the error JOptionPane. This will force it to jump back to the start of the loop and prompt again.

What about for entering miles. If you type something invalid, say a letter, it closes instead of looping. Would i enter another while? I feel like the loop would be weird with that — Javabegin, Oct 08 '15 at 02:11
like I said, if you do need to have it in the loop, you can use `continue;` statements. However, I would suggest you use two loops. — Kaamil Jasani, Oct 10 '15 at 17:09

Need to reprompt a statement, but my code continues to the next statement,

1 Answers1