public boolean isValid(String email) {
        if (email == null) {
            return false;
        }

        if (email.endsWith(".")) { // check this first - it's cheap!
            return false;
        }

        // Check the whole email address structure
        Matcher emailMatcher = EMAIL_PATTERN.matcher(email);
        if (!emailMatcher.matches()) {
            return false;
        }

        if (!isValidUser(emailMatcher.group(1))) {
            return false;
        }

        if (!isValidDomain(emailMatcher.group(2))) {
            return false;
        }

        return true;
    }
public boolean isValid(String email) {
        if (email == null) {
            return false;
        }

        if (email.endsWith(".")) { 
            return false;
        }

        
        Matcher emailMatcher = EMAIL_PATTERN.matcher(email);
        if (!emailMatcher.matches()) {
            return false;
        }

        if (!isValidUser(emailMatcher.group(1))) {
            return false;
        }

        if (!isValidDomain(emailMatcher.group(2))) {
            return false;
        }

        return true;
    }
public boolean isValid ( String email ) { if ( email == null ) { return false ; } if ( email . endsWith ( "." ) ) { // check this first - it's cheap! return false ; } // Check the whole email address structure Matcher emailMatcher = EMAIL_PATTERN . matcher ( email ) ; if ( ! emailMatcher . matches ( ) ) { return false ; } if ( ! isValidUser ( emailMatcher . group ( 1 ) ) ) { return false ; } if ( ! isValidDomain ( emailMatcher . group ( 2 ) ) ) { return false ; } return true ; }
<p>Checks if a field has a valid e-mail address.</p>

@param email The value validation is being performed on.  A <code>null</code>
value is considered invalid.
@return true if the email address is valid.
<p > Checks if a field has a valid e - mail address . < / p >