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.
Example
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);
}
}
Output
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.
Example
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);
}
}
Output
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.
Example
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);
}
}
Output
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.
Example
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);
}
}
Output
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.
Example
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);
}
}
Output
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.
Example
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);
}
}
Output
key: H
key from keyboard: H