Java Program to Check For a Valid Mobile Number

// Java Program to Check For a Valid Mobile Number
import java.util.regex.*;

public class Geeks {
  
    public static void main(String[] args)
    {

        // Example mobile number
        String n = "9991234567";

        // Regular expression to check if
        // the number starts with
        // 7, 8, or 9, followed by 9 digits
        String r = "^[7-9][0-9]{9}$";

        // Check if the number matches
        // the regular expression
        if (n.matches(r)) {
            System.out.println("Valid Mobile Number");
        }
        else {
            System.out.println("Invalid Mobile Number");
        }
    }
}

// Java Program to Check the Indian Mobile Numbers
import java.util.regex.*;

public class ValidateMobileNum {
  
    public static void main(String[] args) {
      
        // Example mobile numbers
        String[] n = { "7873923408", "5678729234" };

        // Regular expression to check if the number starts with 
        // 7, 8, or 9, followed by 9 digits
        String r = "^[7-9][0-9]{9}$";
       
        // Iterate through the numbers and check 
        // if they are valid or invalid
        for (String number : n) {
            if (number.matches(r)) {
                System.out.println(number + ": Valid Mobile Number");
            } else {
                System.out.println(number + ": Invalid Mobile Number");
            }
        }
    }
}

// Java program to Validating Global Mobile Numbers
import java.util.regex.*;

public class GFG {
  
    // Method to check if mobile number is valid
    public static boolean isValid(String s) {
      
        // Regular expression to validate 
        // global mobile numbers
        Pattern p = Pattern.compile(
            "^(\\+\\d{1,3}( )?)?((\\(\\d{1,3}\\))|\\d{1,3})[- .]?\\d{3,4}[- .]?\\d{4}$");
        
        // Matcher to check if the string 
        // matches the regular expression
        Matcher m = p.matcher(s);

        // Returns true if valid, otherwise false
        return (m.matches());
    }

    public static void main(String[] args) {
      
        String s1 = "+1 212 555-3458";
        String s2 = "+4934 351 125-3456"; 

        // Check if both numbers are valid
        if (isValid(s1))
            System.out.println("Valid Mobile Number");
        else
            System.out.println("Invalid Mobile Number");

        if (isValid(s2))
            System.out.println("Valid Mobile Number");
        else
            System.out.println("Invalid Mobile Number");
    }
}