Obtaining Command Line Input in Java
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To obtain console input for your program you can use the Scanner class
First import the relevant library
import java.util.Scanner;
Then create a variable to hold the Scanner object
Scanner input;
input = new Scanner(System.in);
Inside the parenthesis, the Scanner binds to the System input which is by default the console
The new varible input now has the ability to obtain input from the console. To do so, use any of the following methods:
| Method | What it Returns |
|---|---|
next() |
The next space separated string from the console |
nextInt() |
An integer if it exists from the console |
nextDouble() |
A double if it exists from the console |
nextFloat() |
A float if it exists from the console |
nextLine() |
A string up to the next newline character from the console |
hasNext() |
Returns true if there is another token |
close() |
Unbinds the Scanner from the console |
Here is an example program where we get the user’s first name
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);
}
}