How do I return the switch statement inside a do while loop using an instance method?

Question

public void select()
{



do
{
  switch(info)
   {
     case'1':
     case'a':
       return System.out.println("Hello");
     case'2':
     case'b':
       return selection = 'b';
     default:
       return System.out.println("Close");
   }
 }while(info != 'b');
}

So what would be the proper syntax and is this the even possible to do. New to Java

Answer 1

First, the loop is not needed, you can delete that. And you are using return statements wrongly. You cannot return

System.out.println();

Also, your method is declared to return void which means nothing. That means your return statement doesn't need anything else,just the word return.

 return;

So my advice is that print the stuff first, and then return . And you should really read Java for Dummies, by Barry Burd.

Answer 2

1st of all you can't return anything from a void method, instead change it to char for example:

public char select () {
    //read user input
    char userInput = '1'; //change it as you wish or read from console
    switch (userInput) {
        case '1':
        case 'a':
            return 'a';
        case '2':
        case 'b':
            return 'b';
        //... and so on
        default:
            return '0'; //Or anything you want (but it MUST be a char (at least for my code, if you change it to String, you can return a word or well... a String)).
    }
}

Then on main method (or the method which called select() ) you add:

char selection;
selection = select();
System.out.println(selection);

If you want to add the switch into a loop ( do-while as in your question), then you might want to do it this way on main method:

char selection;
do {
    selection = select();
    System.out.println(selection);
} while (selection != '0');

However I strongly recommend you to read Java Docs: Switch Statement and Returning a Value from a method which is actually what you're trying to achieve.

From second link you can confirm what I said before (on the 1st line of my answer and as some other users stated on comments)

Any method declared void doesn't return a value.