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Java Java Objects (Retired) Creating the MVP Prompting for Guesses

Posted by timur sh
timur sh
Courses Plus Student 3,150 Points

java.lang.NullPointerException - i use eclipse and i get this errore

i gote error i line String guessAsString = console.readLine("Enter a letter: ");

import java.io.Console;

public class Prompter {

private Game mGame;

public Prompter(Game game){

   mGame = game;    
}

public boolean promptForGuess(){
    Console console = System.console();
    String guessAsString = console.readLine("Enter a letter:  ");
    char guess = guessAsString.charAt(0);
    return mGame.apllyGuess(guess);
}

}

4 Answers

Vincent Murray
Vincent Murray
11,300 Points
Vincent Murray
Vincent Murray
11,300 Points

If you are using Eclipse 

//import java.io.Console;
import java.util.Scanner;

public class Prompter{

    private Game mGame;

    public Prompter(Game game){
        mGame = game;

    }

    public boolean promptForGuess(){
        //Console console = System.console();
        Scanner kb = new Scanner(System.in);   // kb for Keyboard input can be anything
        //String guessAsString = console.readLine("Enter a letter :");
        String guessAsString = kb.nextLine();
        char guess = guessAsString.charAt(0);
        return mGame.applyGuess(guess);

    }

}

Then enter a letter in the console , and it will return a response

timur sh
PLUS
timur sh
Courses Plus Student 3,150 Points
timur sh
timur sh
Courses Plus Student 3,150 Points

Thank you very much, you've been very helpful.

John Miller
John Miller
4,007 Points
John Miller
John Miller
4,007 Points

Vincent,

Thank you for the information and this did solve my problem, although can you direct me to a resource which can explain to me 'why' I get a NullPointerException when using Console instead of Scanner.

Oshedhe Munasinghe
Oshedhe Munasinghe
8,108 Points
Oshedhe Munasinghe
Oshedhe Munasinghe
8,108 Points

Vincent you saved me :) thanks a lot

Oshedhe Munasinghe
Oshedhe Munasinghe
8,108 Points

Wait a min.. when I complie that window doesnt say anything. I think you have to add System.out.println how do I do that?

anyway when complier runs and if I type just t it works :D