Java中温度转换的操作数错误？

Question

I am doing my first Java assignment and I'm struggling with an error here.

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package ctof;

/**
 *
 * @author Braydon
 */
    import java.util.Scanner;
public class CtoF {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        System.out.println("Enter temperature in Celsius:");
        Scanner temp = new Scanner(System.in);
        String T = scan.nextLine();
            T = (T - 32) * 5/9;
            System.out.println("Temperature in Fahrenheit =" + T);
             }
}

The error it gives me is as follows.

run:
Enter temperature in Celsius:
Exception in thread "main" java.lang.UnsupportedOperationException: Not supported yet.
    at ctof.scan.nextLine(scan.java:19)
    at ctof.CtoF.main(CtoF.java:21)
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)

The error is in the line where I perform the math, but I've tried everything and I can't seem to fix it. Please help!

Answer 1

You're calling the wrong function.

You need to call temp.nextLine() instead of scan.nextLine() in order to read the next line. (scan isn't even defined in the code you posted)

HOWEVER: You shouldn't use nextLine() when you need to read a number.

Therefore: Call temp.nextInt() or temp.nextDouble() instead.

Answer 2

I believe you are newbie to java. First of all, you will have to learn about the data types. Well, you can google basics about programming and learn from it.

The solution for your problem :

public class CtoF {

    public static void main(String[] args) {
        System.out.println("Enter temperature in Celsius:");
        Scanner temp = new Scanner(System.in);
        int T = temp.nextInt();
        T = (T - 32) * 5 / 9;
        System.out.println("Temperature in Fahrenheit =" + T);
    }
}

Try to use good names for the variables (just a suggestion)