Java loop asking for input until user enters something acceptable-CodePudding

as an exercise, I want to create a popup window where user enters a string what I want to achieve:

if they enter yes, print YES

if they enter no, print NO
if they enter something else, loop until they enter yes or no then print YES or NO

1 and 2 work, 3 will loop but then print nothing after yes or no is entered

any ideas?

package harmony.randomstuff;
//imports
import java.text.*;
import java.util.Scanner;
import javax.swing.JOptionPane;


public class RandomStuff {
    public static void main (String[]args) {
       
        //objects
Scanner dakeyboard = new Scanner(System.in);
//************************************************************
String xd = "";

//creates popup window for user to enter something
String x = JOptionPane.showInputDialog("enter (yes\\no)");

// this will loop until you enter yes or no then stop looping but nothing prints
//I tried to express the logic statement "if it is not true that x = yes or x = no then loop until it is

if (!(("yes".equals(x))||("no".equals(x)))) {
    do { x = JOptionPane.showInputDialog("please enter (yes\\no)");
    } while (!(("yes".equals(x))||("no".equals(x))));
}

// the two loops here work perfectly
else if ("yes".equals(x)){
    xd="YES";
}

else if ("no".equals(x)){
    xd="NO";
}

//************************************************************
System.out.println(xd);
 //************************************************************    

        dakeyboard.close();
    }
    
}

CodePudding user response：

simply you can achieve what you want by that

String x ="";
while  (!("yes".equals(x)||"no".equals(x))) {
    x = JOptionPane.showInputDialog("please enter (yes\\no)");
   
}
System.out.println(x.toUpperCase());

CodePudding user response：

the looping is incorrect, instead of else if you should just use if right after this comment // the two loops here work perfectly

package org.rj.stackoverflow;

import java.text.*;
import java.util.Scanner;
import javax.swing.JOptionPane;


public class RandomStuff {
    public static void main(String[] args) {

        //objects
        Scanner dakeyboard = new Scanner(System.in);
//************************************************************
        String xd = "";

//creates popup window for user to enter something
        String x = JOptionPane.showInputDialog("enter (yes\\no)");

// this will loop until you enter yes or no then stop looping but nothing prints
//I tried to express the logic statement "if it is not true that x = yes or x = no then loop until it is

        if (!(("yes".equals(x)) || ("no".equals(x)))) {
            do {
                x = JOptionPane.showInputDialog("please enter (yes\\no)");
            } while (!(("yes".equals(x)) || ("no".equals(x))));
        }

// the two loops here work perfectly
        if ("yes".equals(x)) {
            xd = "YES";
        } else if ("no".equals(x)) {
            xd = "NO";
        }

//************************************************************
        System.out.println(xd);
        //************************************************************

        dakeyboard.close();
    }

}

if you would like to improve code, do below

String x;
do {
   x = JOptionPane.showInputDialog("please enter (yes\\no)");
} while(!x.equals("yes") && !x.equals("no"));
System.out.println(x.toUpperCase());