website/content/blog/2017-08-28-obtaining-command-line-input-java.md

---
id: 2241
title: Obtaining Command Line Input in Java
date: 2017-08-28T17:37:59+00:00
author: Brandon Rozek
layout: post
guid: https://brandonrozek.com/?p=2241
aliases:
    - /2017/08/obtaining-command-line-input-java/
permalink: /2017/08/obtaining-command-line-input-java/
medium_post:
  - 'O:11:"Medium_Post":11:{s:16:"author_image_url";N;s:10:"author_url";N;s:11:"byline_name";N;s:12:"byline_email";N;s:10:"cross_link";N;s:2:"id";N;s:21:"follower_notification";N;s:7:"license";N;s:14:"publication_id";N;s:6:"status";N;s:3:"url";N;}'
mf2_syndicate-to:
  - 'a:1:{i:0;s:4:"none";}'
mf2_cite:
  - 'a:4:{s:9:"published";s:25:"0000-01-01T00:00:00+00:00";s:7:"updated";s:25:"0000-01-01T00:00:00+00:00";s:8:"category";a:1:{i:0;s:0:"";}s:6:"author";a:0:{}}'
tumblr_post_id:
  - "164717769554"
mf2_mp-syndicate-to:
  - 'a:1:{i:0;s:4:"none";}'
kind:
  - note
---
To obtain console input for your program you can use the <code class="language-java">Scanner</code> class

First import the relevant library

<pre class="language-java"><code class="language-java">
import java.util.Scanner;
</code></pre>

Then create a variable to hold the <code class="language-java">Scanner</code> object

<pre class="language-java"><code class="language-java">
Scanner input;
input = new Scanner(System.in);
</code></pre>

Inside the parenthesis, the <code class="language-java">Scanner</code> binds to the System input which is by default the console

The new varible <code class="language-java">input</code> now has the ability to obtain input from the console. To do so, use any of the following methods

<table class="tg">
  <tr>
    <th class="tg-yw4l">
      Method
    </th>

    <th class="tg-yw4l">
      What it Returns
    </th>
  </tr>

  <tr>
    <td class="tg-yw4l">
      next()
    </td>
    
    <td class="tg-yw4l">
      The next space seperated string from the console
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      nextInt()
    </td>
    
    <td class="tg-yw4l">
      An integer if it exists from the console
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      nextDouble()             
    </td>
    
    <td class="tg-yw4l">
      A double if it exists from the console
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      nextFloat()
    </td>
    
    <td class="tg-yw4l">
      A float if it exists from the console
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      nextLine()
    </td>
    
    <td class="tg-yw4l">
      A string up to the next newline character from the console
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      hasNext()
    </td>
    
    <td class="tg-yw4l">
      Returns true if there is another token
    </td>
  </tr>

  <tr>
    <td class="tg-yw4l">
      close()
    </td>
    
    <td class="tg-yw4l">
      Unbinds the Scanner from the console
    </td>
  </tr>
</table>

Here is an example program where we get the user&#8217;s first name

<pre class="language-java"><code class="language-java">
import java.util.Scanner;

public class GetName {
  public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    System.out.print("Please enter your name: ");
    String firstName = input.next();
    System.out.println("Your first name is " + firstName); 
  }
}
</code></pre>