Question

Java Branches code not working please HELP!!

I am trying to build this class that will ask for an ingredient, and the number of cups of the ingredient. It should then branch into an if/else branch off to verify that the number entered is valid and that it is within range. Once that branch completes it should then continue on to ask for the calories per cup, and then calculate total calories. Once I get it to enter the branch though I get a compile error and the program terminates. I am not sure how to nest the branch in with the rest of the code I guess. Thank you in advance to anyone that can help me out with this!

The code is below:

package ingedientclass;

import java.util.Scanner;

/**
*
* @author
*/

public class IngedientClass {

  
public static void main(String[] args) {
String nameOfIngredient = "";
double numCups = 0;
int numCaloriesPerCup = 0;
double totalCalories = 0.0;
final int MAX_CUPS = 100;

Scanner scnr = new Scanner(System.in);


System.out.println("Please enter the name of the ingredient: ");
nameOfIngredient = scnr.next();


System.out.println("Please enter the number of cups of "
+ nameOfIngredient + " we'll need: ");
numCups = scnr.nextFloat();

if (numCups > 1 && numCups <= MAX_CUPS){
System.out.println(numCups + " is a valid number of cups");
} else{
System.out.println(numCups + " is not a valid number of cups!");
System.out.println("Please enter a number of cups between 1 and 100:");
numCups = scnr.nextInt();
if (numCups >= 1 && numCups <= MAX_CUPS){
System.out.println(numCups + " is a valid number of cups!");
} else if(numCups <1){
System.out.println(numCups + " is less than 1. Sorry you are out of tries.");
} else if (numCups > 100) {
System.out.println(numCups + " is larger than 100. Sorry you are out of tries.");
}
}
}else{

System.out.println("Error: That is not a number.");

}

System.out.println("Please enter the number of calories per cup: ");
numCaloriesPerCup = scnr.nextInt();


totalCalories = (numCaloriesPerCup * numCups);
  
System.out.println("The total number of calories is " + totalCalories);

}
  

Answer 1

Here is the corrected code for this problem. Comments are included, go through it, learn how things work and let me know if you have any doubts or if you need anything to change. If you are satisfied with the solution, please rate the answer. Thanks

Note: This could be much better if you are allowed to use a loop for validation, in that way, you could get rid of repeating statements to shorten the nested if else block. Let me know if you need. Also, the case of non numeric entry won’t be executed as there is no exception handler setup.

// IngedientClass.java

package ingeredientclass;

import java.util.Scanner;

public class IngedientClass {

              public static void main(String[] args) {

                           String nameOfIngredient = "";

                           double numCups = 0;

                           int numCaloriesPerCup = 0;

                           double totalCalories = 0.0;

                           final int MAX_CUPS = 100;

                           Scanner scnr = new Scanner(System.in);

                           System.out.println("Please enter the name of the ingredient: ");

                           nameOfIngredient = scnr.next();

                           System.out.println("Please enter the number of cups of "

                                                       + nameOfIngredient + " we'll need: ");

                           // getting initial value for number of cups

                           numCups = scnr.nextFloat();

                           // validation

                           if (numCups > 1 && numCups <= MAX_CUPS) {

                                         // valid

                                         System.out.println(numCups + " is a valid number of cups");

                           } else {

                                         // invalid, asking for one more time

                                         System.out.println(numCups + " is not a valid number of cups!");

                                         System.out

                                                                    .println("Please enter a number of cups between 1 and 100:");

                                         numCups = scnr.nextInt();

                                         // validating again

                                         if (numCups >= 1 && numCups <= MAX_CUPS) {

                                                       // valid

                                                       System.out.println(numCups + " is a valid number of cups!");

                                         } else if (numCups < 1) {

                                                       // invalid, displaying error message and quitting

                                                       System.out.println(numCups

                                                                                  + " is less than 1. Sorry you are out of tries.");

                                                       System.exit(0); // end of program

                                         } else if (numCups > 100) {

                                                       System.out.println(numCups

                                                                                  + " is larger than 100. Sorry you are out of tries.");

                                                       System.exit(0);// end of program

                                         }

                           }

                           // if the program reached here, the number of cups is valid, so asking

                           // for number of calories per cup

                           System.out.println("Please enter the number of calories per cup: ");

                           numCaloriesPerCup = scnr.nextInt();

                           // not validating number of calories per cup since not mentioned.

                           totalCalories = (numCaloriesPerCup * numCups);

                           System.out.println("The total number of calories is " + totalCalories);

              }

}

/*OUTPUT*/

Please enter the name of the ingredient:

mocha

Please enter the number of cups of mocha we'll need:

2400

2400.0 is not a valid number of cups!

Please enter a number of cups between 1 and 100:

99

99.0 is a valid number of cups!

Please enter the number of calories per cup:

3

The total number of calories is 297.0