Check if Email Address is Valid or not in Java

Given a string, find if the given string is a valid email or not.

Input : email = "review-team@geeksforgeeks.org"
Output : Yes

Input : email = "contribute@geeksforgeeks..org"
Output : No
Explanation : There is an extra dot(.) before org.

Prerequisite: Regular Expressions in Java

Regular Expressions 

Regular Expressions or Regex is an API for defining String patterns that can be used for searching, manipulating, and editing a string in Java. Email validation and passwords are a few areas of strings where Regex is widely used to define the constraints. Regular Expressions are provided under java.util.regex package. 

In order to check that an email address is valid or not, we use the below-given regular expression provided in the OWASP Validation Regex repository.

^[a-zA-Z0-9_+&*-] + (?:\\.[a-zA-Z0-9_+&*-]
+ )*@(?:[a-zA-Z0-9-]+\\.) + [a-zA-Z]{2, 7}$ 

Code – 

Java

// Java program to check if an email address
// is valid using Regex.
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.*;

class Test
{
    public static boolean isValid(String email)
    {
        String emailRegex = "^[a-zA-Z0-9_+&*-]+(?:\\."+
                            "[a-zA-Z0-9_+&*-]+)*@" +
                            "(?:[a-zA-Z0-9-]+\\.)+[a-z" +
                            "A-Z]{2,7}$";

        Pattern pat = Pattern.compile(emailRegex);
        if (email == null)
            return false;
        return pat.matcher(email).matches();
    }

    public static void main(String[] args)
    {
        ArrayList<String> address = new ArrayList<>();

          address.add("review-team@geeksforgeeks.org");
          address.add("writing.geeksforgeeks.org");

        for(String i : address){
            if (isValid(i))
                System.out.println(i + " - Yes");
            else
                System.out.println(i + " - No");
        }
    }
}

Output

review-team@geeksforgeeks.org - Yes
writing.geeksforgeeks.org - No

This article is contributed by Pranav. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.