Java Scanner Input Loop

Question

I've got a loop that is controlled by a variable called running which tells if the program is running or not. I am trying to achieve a loop that the user enters a command, and the program is answering him, but for some reason, It's seems like my String splits if its more than one word, this is what I have tried:

import java.util.Scanner;
public class ScannerTest{
    private boolean running = true;
    public ScannerTest(){
        Scanner s = new Scanner(System.in);
        while(running){
           String command = s.next();
           System.out.println(command);
        }
    }
}

If I am entering two or more words in the Scanner, It seems to split them.

Input  >> Hello what's your name?
Output >> Hello
       >> what's
       >> your
       >> name?

Maybe it's because of the While loop? How can i fix it? Thanks in advance.

Hovercraft Full Of Eels · Accepted Answer · 2013-10-20 20:48:48Z

4

Scanner#next() does just this -- it grabs the next token defined by any white-space delimiter(s), and does not get the next line. If your words have white space between them, it will grab the individual words one at a time with each invocation of the method.

Use Scanner#nextLine() instead if you want to grab the complete line that the user entered.

Edit: this question has to be a duplicate of another somewhere on this site.

answered Oct 20, 2013 at 20:48

Hovercraft Full Of Eels

286k25 gold badges267 silver badges391 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Prabhakaran Ramaswamy · Accepted Answer · 2013-10-20 20:55:58Z

0

next() method will split your input by space delimiter.

nextLine() method will fix your problem. nextLine(); will read the entire line at once.

Replace String command = s.next(); to String command = s.nextLine();

edited Oct 20, 2013 at 20:55

answered Oct 20, 2013 at 20:49

Prabhakaran Ramaswamy

26.1k10 gold badges61 silver badges65 bronze badges

1 Comment

itsols Over a year ago

But how does this work if you need to get integer inputs in a loop? I noticed that nextInt seems to skip an input because of a RETURN character (I presume).

Mazino · Accepted Answer · 2015-04-09 22:48:45Z

0

You're using

System.out.println();

just use

System.out.print();

only use println if you want the next output/input to be entered onto the next line.

answered Apr 9, 2015 at 22:48

Mazino

5626 silver badges27 bronze badges

Comments

Community · Accepted Answer · 2017-05-23 12:24:22Z

0

Why don't you use end-of-file indicator, the loop you used in your solution is called sentinel-controlled repetition the I think the better value to control it is by using end-of-file indicator take look at my answer java Scanner.hasNext() usage

edited May 23, 2017 at 12:24

CommunityBot

11 silver badge

answered Feb 9, 2017 at 8:02

Basheer AL-MOMANI

15.5k9 gold badges103 silver badges96 bronze badges

Collectives™ on Stack Overflow

Java Scanner Input Loop

4 Answers 4

Comments

1 Comment

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related