Have a function take some data and send it back

Question

I'm trying to make a java function take some input, change it and send it back. Normally you would have return varName; or something however here it is not working. My question is this: how can I make a custom method to take in a variable 'nameRaw' and change it within the function 'nameChanger()' then out put the changed name to variable: 'nameChanged'.

I have used IDEONE.com to show the code and process it, so here is the link: http://ideone.com/cdj6Cd

If you do not trust random links, that's find and completely understandable. So, I'll also put it here but just assume the only thing the user has typed as the input is "Test".

Code:

/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
    public static void main (String[] args) throws java.lang.Exception {
        System.out.println("*INTENDED* Function of this-To create a custom method to take in a variable 'nameRaw' and change it within the function 'nameChanger()' then out put the changed name to variable: 'nameChanged'.\nProblem: the name changes within the function 'nameChanger()' only, therefore I cannot call the variable 'nameChanged' elsewhere, such as in main().........\n\n\n");
        // Initalize the Java Scanner
        Scanner in = new Scanner(System.in);

        // Initalizes a completely empty string with name "nameChanged"
        String nameChanged = null;

        System.out.println("Please enter a username for yourself below:");
        System.out.println("Test"); // Fake input to make me feel good I guess, it just looks better

        // Sets "nameRaw" to "Test"
        String nameRaw = in.nextLine();

        // Spits out the untouched value that the user has entered
        System.out.println("\nRaw name before passing to custom method: " + nameRaw);

        // Puts "nameRaw" into the custom method "nameChanger()" to change the, "s" in, "Test" to a "z" by default
        nameChanger(nameRaw, nameChanged);

        // Spits out the touched and changed nameChanged variable from "nameChanger()"
        if(nameChanged == null) {
            System.out.println("\nHere is the failed changed name: " + nameChanged);
            System.out.println("\nARE YOU KIDDING ME! WHY DOES THIS NOT WORK?!?! PLEASE HELP!!!!");
        } else {
            System.out.println("Here is the successfuly changed name: " + nameChanged);
            System.out.println("\nWhoever solved this problem is a god..");
        }

    } // Closes method main()

    // Custom method named "nameChanger" that will need a variable named "nameRaw" *which is set* within its () to function
    private static String nameChanger(String nameRaw, String nameChanged) {

        //// Initalizes a completely empty string with name "nameChanged"
        //String nameChanged = null;

        // States the set name *unchanged* from the main method on line 17
        System.out.println("\t#\tName unchanged read and displayed by the nameChanger custom method: " + nameRaw);

        // The name by default "Test" does contain an "s" so the if statement is satisfied
        if(nameRaw.contains("s")) {

            // The variable "nameRaw should be running through here and having it's "s" replaced with a "z"
            nameChanged = nameRaw.replace("s", "z");

            // Output the changed name *if all goes right*
            System.out.println("\t#\tName changed *still in custom function* is: " + nameChanged);

        // The else statement is just for testing purposes, such as changing "Test" as the input to "Demo" to dis-satisfy the if statemtent 
        } else {
            System.out.println("\t#\tFor reference, here is the unchanged name raw: " + nameRaw);
            System.out.println("\t#\tAlso for reference, here is the null value 'nameChanged': " + nameChanged);
        }

        // One more time to show my hate toward Java, output the changed variable "nameChanged". Take note that the "s" is a "z".....
        System.out.println("\t#\tPlease don't be null or have an 's' in it: " + nameChanged);

        // To output to main() that nameChanged is now not null *if all goes right*, but "Tezt" should be the output
        return nameChanged;
    } // Close custom method, nameChanger()
}

Thanks guys hope this doesn't overwhelm you toooo much :p, Aaron

Answer 1

private static String nameChanger(String nameRaw, String nameChanged) in this method, why are you passing nameChanged? I think nameChanged should be the value returned at the end of the nameChanger method.

I don't understand why you are checking if the nameChanged is null yet you initialized it as null and didn't change it.

String nameChanged = null;


if(nameChanged == null) {
        System.out.println("\nHere is the failed changed name: " + nameChanged);
        System.out.println("\nARE YOU KIDDING ME! WHY DOES THIS NOT WORK?!?! PLEASE HELP!!!!");
    } else {
        System.out.println("Here is the successfuly changed name: " + nameChanged);
        System.out.println("\nWhoever solved this problem is a god..");
    }

If you still go by your method, try nameChanged = nameChanger(nameRaw, nameChanged) instead of nameChanged = null

I hope this helps