mirror of
https://github.com/Brandon-Rozek/website.git
synced 2024-11-09 18:50:34 -05:00
136 lines
3.2 KiB
Markdown
136 lines
3.2 KiB
Markdown
|
---
|
|||
|
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
|
|||
|
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’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>
|