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Java

Posted by Abdullah Nazeer
Abdullah Nazeer
239 Points

what's wrong with my code?

import java.io.Console;

public class TreeStory {

public static void main(String[] args) {
    Console console = System.console();
  String ageAsString= console.readLine(" How old are you"   );

  int age=Integer.parseInt(ageAsString);
  if(age<13)
  {console.printf("Sorry you can't use this site\n");
  System.exit(0);}
  }

}

1 Answer

Fergus Clare
Fergus Clare
12,120 Points
Fergus Clare
Fergus Clare
12,120 Points

Hey Abdullah Nazeer! Great work on getting into JAVA! I think the problem is that you're trying to assign the string value of ageAsString directly from readLine instead using readLine to assign a value after the System.out.print prompts the user for a command. That's why you would be getting a nullPointerException. Consider the following code which worked well for me (compiled with no errors and is able to check for your conditions):

import java.io.Console; //import io

public class Test { //test class saved and named as Test.java for testing on JVM(you can ignore this part if using treehouse)
    public static void main (String[] args) {
        Console console = System.console(); //create a new console object
        System.out.print("Enter your age:  "); //prompt the user for their age
        String ageAsString= console.readLine(); //store the input of the user in value "ageAsString

        int age=Integer.parseInt(ageAsString); //read the string value using parseInt and assign value to new variable
        if (age < 13) {//if the user is under age 13
            console.printf("Sorry you can't use this site\n");//let them know they can't enjoy the site
            System.exit(0);//close program
        }//end if 
    }//end main method
}//end class

It's also good practice to either format your brackets like so in order to make code more readable:

//example of proper formatting for opening/closing braces 1
if (exampleCondition1 > exampleCondition2) {
   yourCodeGoesHere;
}
//example of proper formatting for opening/closing braces 2
if (exampleCondition1 > exampleCondition2) 
{
   yourCodeGoesHere;
}

Keep up the good work! You're doing great!