Need help with calling method

Question

I'm new to Java, trying to pass a required class so I can graduate this semester, and I need help figuring out what is wrong with the code below. My assignment is to create a program to convert celsius to fahrenheit and vice versa using Scanner for input. The program must contain 3 methods - main, convert F to C, method, and convert C to F method. Requirements of the conversion methods are one parameter which is an int representing temp, return an int representing calculated temp after doing appropriate calculation, should not display info to user, and should not take in info from user.
The main method is required to ask the user to input a 1 for converting F to C, 2 for C to F, and 3 to end the program. It must include a while loop that loops until the user enters a 3, ask the user to enter a temp, call the appropriate method to do the conversion, and display the results. I'm having trouble calling the conversion methods and keep getting the following 2 compiler errors:
cannot find symbol
symbol : method farenheitToCelsius(int)
location: class WondaPavoneTempConverter
int celsius = farenheitToCelsius(intTemp);
^
cannot find symbol
symbol : method celsiusToFarenheit(int)
location: class WondaPavoneTempConverter
int farenheit = celsiusToFarenheit(intTemp);
The code is as follows:
public static void main(String[] args) {
// Create a scanner
Scanner scanner = new Scanner(System.in);
// Prompt the user to enter a temperature
System.out.println("Enter the temperature you wish to convert as a whole number: ");
int intTemp = scanner.nextInt();
System.out.println("You entered " + intTemp + " degrees.");
// Prompt the user to enter "1" to convert to Celsius, "2" to convert to
// Farenheit, or "3" to exit the program
System.out.println("Enter 1 to convert to Celsius, 2 to convert to Farenheit, or 3 to exit.");
int intConvert = scanner.nextInt();
// Convert temperature to Celsius or Farenheit
int celsius = farenheitToCelsius(intTemp);
int farenheit = celsiusToFarenheit(intTemp);
while (intConvert >= 0) {
// Convert to Celsius
if (intConvert == 1) {
System.out.println("Celsius is " + celsius + " degrees.");
// Convert to Farenheit
else if (intConvert == 2) {
System.out.println("Farenheit is " + farenheit + " degrees.");
// Exit program
else if (intConvert == 3) {
break;
else {
System.out.println("The number you entered is invalid. Please enter 1, 2, or 3.");
//Method to convert Celsius to Farenheit
public static int celsiusToFahrenheit(int cTemp) {
return (9 / 5) * (cTemp + 32);
//Method to convert Farenheit to Celsius
public static int fahrenheitToCelsius(int fTemp) {
return (5 / 9) * (fTemp - 32);
I readily admit I'm a complete dunce when it comes to programming - digital media is my area of expertise. Can anyone point me in the right direction? This assignment is due very soon. Thanks.

Answer 1

1) consider using a boolean variable in the while statement and converting it to true if the input is good.
while (inputNotValid)
}2) put the code to get the input within the while loop. Try your code right now and enter the number 30 when your menu requests for input and you'll see the infinite loop.... and why you need to request input within the loop.
3) Fix your equations. You are gonig to have to do some double calcs, even if you convert it back to int for the method return. Otherwise the results are just plain wrong. As a good test, put in the numbers -40, 0, 32, 100, and 212. Are the results as expected? (-40 is the only temp that is the same for both cent and fahr). I recommend doing double calcs and then casting the result to int in the return. for example:
int a = (int) (20 + 42.0 / 3);  // the 42.0 forces the compiler to do double calc.4) One of your equations may still be plain wrong even with this fix. Again, run the test numbers and see.
5) Also, when posting your code, please use code tags so that your code will be well-formatted and readable. To do this, either use the "code" button at the top of the forum Message editor or place the tag [code] at the top of your block of code and the tag [/code] at the bottom, like so:
[code]
  // your code block goes here.
[/code]