Creating folder by user entering name

Question

I am trying to create a folder by having a user typing the name of the folder:

Scanner scanner;
String inputUser;

public void createDir(String input){
    System.out.print("Please enter name of Folder: ");
    this.inputUser = this.scanner.next().toUpperCase();

    File makeDir = new File("C:\\" + this.inputUser);

    try{
        if(!makeDir.exists()){
            makeDir.mkdir();
            System.out.println("You have created directory " + makeDir.getName());
        }else{
            System.out.println("Directory with name " + makeDir.getName() + " already exists.");
        }
    }catch(Exception e){
        System.out.println("Error while creating directory name " + makeDir.getName());
    }
}

but every time when I run it I am getting the following error message:

Exception in thread "main" java.lang.NullPointerException Please enter name of Folder: at filemanagerapp.FileManagerSystem.createDir(FileManagerSystem.java:68) at filemanagerapp.FileManagerApp.main(FileManagerApp.java:42)

Java Result: 1

I have noticed that the line that is causing the problem is this.inputUser as when I remove it and try hard coding the name of folder to create, it creates normally with no problem, but I want user to enter name of folder if possible.

Can anyone tell me why this error is happening?

`scanner` is `null` or you left out the code that initializes it — OneCricketeer, Jan 29 '16 at 18:36

score 0 · Accepted Answer · answered Jan 29 '16 at 18:39

0

Replace Scanner scanner with Scanner scanner = new Scanner(System.in)

answered Jan 29 '16 at 18:39

Atri

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Thank you Atri, totally missed to enter full scanner class .... so simple but effective :) – Denis Jan 29 '16 at 18:51

Abdelhak · Answer 2 · 2016-01-30T00:58:53.653

0

Try to add Scanner:

  Scanner scanner = new Scanner(System.in);
  inputUser = scanner.next().toUpperCase();

edited Jan 30 '16 at 00:58

answered Jan 29 '16 at 18:39

Abdelhak

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4
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Creating folder by user entering name

2 Answers2