How to read user input in Java

We use the Scanner class to read user input. It is located in java.util package. We need to import it before we use it.

Creation / Declaration Scanner Object

System.in is the parameter passed to the Scanner constructor so that Java will know to connect the new Scanner to the keyboard.

import java.util.Scanner;

public class createScannerObject {

    public static void main(String[] args) {

            Scanner scanner=new Scanner(System.in);

    }
}

Scanner Class Methods

Read Integer User Input

import java.util.Scanner;

public class getIntUserInput {

    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        System.out.println("Enter some integer number:\n");
        int num=scanner.nextInt();
        System.out.println("You entered this number: "+num);

    }
}

Read Decimal User Input

import java.util.Scanner;

public class getDoubleUserInput {

    public static void main(String[] args) {

        Scanner scanner=new Scanner(System.in);
        System.out.println("Enter some decimal number:\n");
        double num=scanner.nextDouble();
        System.out.println("You entered this number: "+num);
    }
}

Read String User Input

import java.util.Scanner;

public class getStringUserInput {

    public static void main(String[] args) {

        Scanner scanner=new Scanner(System.in);
        System.out.println("Enter your name:");
        String name=scanner.next();

        //scanner.nextLine();
        System.out.println("Enter your surname:");
        String surname=scanner.next();

        System.out.println("Your name: "+name);
        System.out.println("Your surname: "+surname);

    }
}

Read String and Number Same Time

import java.util.Scanner;

public class getNumberAndString {

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

        System.out.println("Enter your age:");
        int age=scanner.nextInt();

        //if we use nextLine method after next method.
        //we add one more nextLine method because to clear Scanner memory.
        scanner.nextLine();

        System.out.println("Enter your full name:");
        String fullName=scanner.nextLine();

        System.out.println("Full name: "+fullName);
        System.out.println("Age: "+age);
    }
}

Note: Please find the practice Java project on below GitHub link: https://github.com/azatbayram/GetUserInput