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Java

drew s
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drew s
Python Development Techdegree Graduate 19,491 Points
Posted by drew s
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drew s
Python Development Techdegree Graduate 19,491 Points

Not running

import java.io.Console;

public class Introductions {

    public static void main(String[] args) {
        Console console = System.console();
        // Welcome to the Introductions program!  Your code goes below here
        console.printf("Hello, my name is Felix");
  }
}

I am getting this Error:

Exception in thread "main" java.lang.NullPointerException
    at Introductions.main(Introductions.java:18)

5 Answers

Chris Shearon
PLUS
Chris Shearon
Courses Plus Student 17,330 Points
Chris Shearon
Chris Shearon
Courses Plus Student 17,330 Points

It's possible for the console object to be null. NullPointerException can be thrown when calling a method on a null object. You can do a simple test for null.

Console console = System.console();
        if (console != null) {
            //safe to call method
            console.printf("console object is not null");
        }else {
            System.out.println("console object is null");
        }
Lauren Moineau
Lauren Moineau
9,483 Points
Lauren Moineau
Lauren Moineau
9,483 Points

You might want to use Scanner instead of Console in VS. I know some IDEs react with a NPE when using Console. Try:

import java.util.Scanner;

public class Introductions {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        // Welcome to the Introductions program!  Your code goes below here
        System.out.printf("Hello, my name is Felix");
  }
}

Hope that helps :)

drew s
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
drew s
Python Development Techdegree Graduate 19,491 Points
drew s
.a{fill-rule:evenodd;}techdegree seal-36
drew s
Python Development Techdegree Graduate 19,491 Points

I tried using scanner it works a little but its not functional compared to treehouse workspaces. Do you know any good IDE for Java?

Lauren Moineau
Lauren Moineau
9,483 Points

You can try IntelliJ. The Community edition is free. I'm not familiar with Visual Studio, but I've never had any problem with Scanner on IntelliJ.

Chris Shearon
Chris Shearon
Courses Plus Student 17,330 Points

There's several perfectly good choices out there but Intellij is my personal favorite.

Lauren Moineau
Lauren Moineau
9,483 Points

Same here :)

Lauren Moineau
Lauren Moineau
9,483 Points

OK. You're welcome :)