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

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---
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
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- /2017/08/obtaining-command-line-input-java/
permalink: /2017/08/obtaining-command-line-input-java/
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kind:
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---
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>