Assign Keyboard Input to Variables in Java

In this article, we discuss how to read data from the keyboard in Java.

Read String Value from Keyboard

You can use nextLine method to input an string value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		String username;
		System.out.print("username: ");
		username = scanner.nextLine();
		System.out.println("username from keyboard: " + username);
	}
}
username: acc1
username from keyboard: acc1	
   

Read Int Value from Keyboard

You can use nextInt method to input an integer value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		System.out.print("id: ");
		int id = scanner.nextInt();
		System.out.println("id from keyboard: " + id);
	}
}
id: 123
id from keyboard: 123	
 

Read Float Value from Keyboard

You can use nextFloat method to input an float value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		float tempDegree;
		System.out.print("tempDegree: ");
		tempDegree = scanner.nextFloat();
		System.out.println("tempDegree from keyboard: " + tempDegree);
	}
}
tempDegree: 5.6
tempDegree from keyboard: 5.6
 

Read Double Value from Keyboard

You can use nextDouble method to input an double value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		double price;
		System.out.print("price: ");
		price = scanner.nextDouble();
		System.out.println("price from keyboard: " + price);
	}
}
price: 2567.54
price from keyboard: 2567.54	

Best Keyboards For Programming

Read Boolean Value from Keyboard

You can use nextBoolean method to input an boolean value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		boolean status;
		System.out.print("status: ");
		status = scanner.nextBoolean();
		System.out.println("status from keyboard: " + status);
	}
}
status: true
status from keyboard: true	
 

Read Char Value from Keyboard

You can use next and charAt method to input an character value from the user and assign it to the variable.

package octopuscodes.com.demo;

import java.util.Scanner;

public class Demo {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);

		char key;
		System.out.print("key: ");
		key = scanner.next().charAt(0);
		System.out.println("key from keyboard: " + key);
	}
}
key: H
key from keyboard: H