[Hanan Mahammed]

السلام عليكم ورحمة الله بركاته
عزيزتي اليك الحل بأبسط طريقة وعذرا على الرد المتأخر

package javaapplication14;

/**
 *
 * @author Hanan
 */
import java.util.Scanner;
public class AgeProgram {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        // TODO code application logic here
        Scanner input=new Scanner(System.in);
         System.out.println("Welcome");
                  System.out.println("                                ");

        System.out.println("Please enter your age :");
        int age = input.nextInt();
        
        
        
        switch ( age) {
case 0: case 1:  case 2: case 3:  case 4:  case 5: case 6:  case 7:  case 8: case 9:  case 10: 
    System.out.println("Your age is between 0 to 10");
   break;
        case 11: case 12:  case 13: case 14:  case 15:  case 16: case 17:  case 18:  case 19:
              System.out.println("Your age is between 11 to 19");
   break;
            case 20: case 21:  case 22: case 23:  case 24:  case 25: case 26:  case 27:  case 28: case 29: case 30:
              System.out.println("Your age is between 20 to 30");
   break;       
            default:
                 System.out.println("Your age is more than 30");
                                        
                                    
}
        System.out.println("                 ");
        System.out.println("Thanks for using our program");
    }        }

ليست الطريقة الافضل لكنها الأبسط للمبتدئين
وبالتوفيق ..*