在这里，程序要求用户输入一个数字。在此之后，程序打印数字的数字和数字的和。

import java.util.Scanner;

public class PrintNumber {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int num = 0;
        int sum = 0;

        System.out.println(
            "Please enter a number to show its digits");
        num = scan.nextInt();

        System.out.println(
            "Here are the digits and the sum of the digits");
        while (num > 0) {
            System.out.println("==>" + num % 10);
            sum += num % 10;
            num = num / 10;   
        }
        System.out.println("Sum is " + sum);            
    }
}

import java.util.Scanner;

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

        System.out.print("Name : ");
        String name = input.next();
        System.out.print("Last Name : ");
        String lname = input.next();
        System.out.print("Age : ");
        byte age = input.nextByte();

        System.out.println(" " );
        System.out.println(" " );

        System.out.println("Firt Name: " + name);
        System.out.println("Last Name: " + lname);
        System.out.println("      Age: " + age);
    }
}

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        System.out.println("Welcome to the best program in the world! ");
        while (true) {
            System.out.print("Enter a query: ");
            Scanner scan = new Scanner(System.in);
            String s = scan.nextLine();
            if (s.equals("q")) {
                System.out.println("The program is ending now ....");
                break;
            } else  {
                System.out.println("The program is running...");
            }
        }
    }
}

class ex1 {    
    public static void main(String args[]){
        int a, b, c;
        a = Integer.parseInt(args[0]);
        b = Integer.parseInt(args[1]);
        c = a + b;
        System.out.println("c = " + c);
    }
}
// Output  
javac ex1.java
java ex1 10 20 
c = 30

Scanner input=new Scanner(System.in);
int integer=input.nextInt();
String string=input.next();
long longInteger=input.nextLong();

import java.util.Scanner; 

class Daytwo{
    public static void main(String[] args){
        System.out.println("HelloWorld");

        Scanner reader = new Scanner(System.in);
        System.out.println("Enter the number ");

        int n = reader.nextInt();
        System.out.println("You entered " + n);

    }
}