CODEWITHSUNDEEP
javaregex
Ducky
Ducky

Reputation: 191

Java Regular Expressions to Validate phone numbers

In the following code I am trying to get the output to be the different formatting of phone numbers and if it is either valid or not. I figured everything out but the Java Regular Expression code on line 11 the string pattern.

 import java.util.regex.*;

  public class MatchPhoneNumbers {
   public static void main(String[] args) {           
     String[] testStrings = {               
               /* Following are valid phone number examples */             
              "(123)4567890", "1234567890", "123-456-7890", "(123)456-7890",
              /* Following are invalid phone numbers */ 
              "(1234567890)","123)4567890", "12345678901", "(1)234567890",
              "(123)-4567890", "1", "12-3456-7890", "123-4567", "Hello world"};

             // TODO: Modify the following line. Use your regular expression here
              String pattern = "^/d(?:-/d{3}){3}/d$";    
             // current pattern recognizes any string of digits           
             // Apply regular expression to each test string           
             for(String inputString : testStrings) {
                System.out.print(inputString + ": "); 
                if (inputString.matches(pattern)) {     
                    System.out.println("Valid"); 
                } else {     
                    System.out.println("Invalid"); 
                }
             }
      }
  }

Upvotes: 16

Views: 82931

Answers (5)

Ashish Lahoti
Ashish Lahoti

Reputation: 1008

Considering these facts about phone number format:-

  1. Country Code prefix starts with ‘+’ and has 1 to 3 digits
  2. Last part of the number, also known as subscriber number is 4 digits in all of the numbers
  3. Most of the countries have 10 digits phone number after excluding country code. A general observation is that all countries phone number falls somewhere between 8 to 11 digits after excluding country code.
String allCountryRegex = "^(\\+\\d{1,3}( )?)?((\\(\\d{1,3}\\))|\\d{1,3})[- .]?\\d{3,4}[- .]?\\d{4}$";

Let's break the regex and understand,

  • ^ start of expression
  • (\\+\\d{1,3}( )?)? is optional match of country code between 1 to 3 digits prefixed with '+' symbol, followed by space or no space.
  • ((\\(\\d{1,3}\\))|\\d{1,3} is mandatory group of 1 to 3 digits with or without parenthesis followed by hyphen, space or no space.
  • \\d{3,4}[- .]? is mandatory group of 3 or 4 digits followed by hyphen, space or no space
  • \\d{4} is mandatory group of last 4 digits
  • $ end of expression

This regex pattern matches most of the countries phone number format including these:-

        String Afghanistan      = "+93 30 539-0605";
        String Australia        = "+61 2 1255-3456";
        String China            = "+86 (20) 1255-3456";
        String Germany          = "+49 351 125-3456";
        String India            = "+91 9876543210";
        String Indonesia        = "+62 21 6539-0605";
        String Iran             = "+98 (515) 539-0605";
        String Italy            = "+39 06 5398-0605";
        String NewZealand       = "+64 3 539-0605";
        String Philippines      = "+63 35 539-0605";
        String Singapore        = "+65 6396 0605";
        String Thailand         = "+66 2 123 4567";
        String UK               = "+44 141 222-3344";
        String USA              = "+1 (212) 555-3456";
        String Vietnam          = "+84 35 539-0605";

Source:https://codingnconcepts.com/java/java-regex-for-phone-number/

Upvotes: 8

Anurag Gupta
Anurag Gupta

Reputation: 59

international phone number regex

String str=  "^\\s?((\\+[1-9]{1,4}[ \\-]*)|(\\([0-9]{2,3}\\)[ \\-]*)|([0-9]{2,4})[ \\-]*)*?[0-9]{3,4}?[ \\-]*[0-9]{3,4}?\\s?";


 if (Pattern.compile(str).matcher(" +33 - 123 456 789 ").matches()) {
        System.out.println("yes");
    } else {
        System.out.println("no");
    }

Upvotes: 5

ankit MISHRA
ankit MISHRA

Reputation: 86

The regex that you need is:

String regEx = "^\\(?(\\d{3})\\)?[- ]?(\\d{3})[- ]?(\\d{4})$";

Regex explanation:

^\\(? - May start with an option "("

(\\d{3}) - Followed by 3 digits

\\)? - May have an optional ")"

[- ]? - May have an optional "-" after the first 3 digits or after optional ) character

(\\d{3}) - Followed by 3 digits.

[- ]? - May have another optional "-" after numeric digits

(\\d{4})$ - ends with four digits

Upvotes: 3

Patrick Parker
Patrick Parker

Reputation: 4959

Basically, you need to take 3 or 4 different patterns and combine them with "|":

String pattern = "\\d{10}|(?:\\d{3}-){2}\\d{4}|\\(\\d{3}\\)\\d{3}-?\\d{4}";
  • \d{10} matches 1234567890
  • (?:\d{3}-){2}\d{4} matches 123-456-7890
  • \(\d{3}\)\d{3}-?\d{4} matches (123)456-7890 or (123)4567890

Upvotes: 24

Elliott Frisch
Elliott Frisch

Reputation: 201447

Create a non-capturing group for three digits in parenthesis or three digits (with an optional dash). Then you need three digits (with another optional dash), followed by four digits. Like, (?:\\(\\d{3}\\)|\\d{3}[-]*)\\d{3}[-]*\\d{4}. And you might use a Pattern. All together like,

String[] testStrings = {
        /* Following are valid phone number examples */         
        "(123)4567890", "1234567890", "123-456-7890", "(123)456-7890",
        /* Following are invalid phone numbers */
        "(1234567890)","123)4567890", "12345678901", "(1)234567890",
        "(123)-4567890", "1", "12-3456-7890", "123-4567", "Hello world"};

Pattern p = Pattern.compile("(?:\\(\\d{3}\\)|\\d{3}[-]*)\\d{3}[-]*\\d{4}");
for (String str : testStrings) {
    if (p.matcher(str).matches()) {
        System.out.printf("%s is valid%n", str);
    } else {
        System.out.printf("%s is not valid%n", str);    
    }
}

Upvotes: 1

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