Java ~ check Email Validation ~ verify email

source
http://www.zparacha.com/ultimate-java-regular-expression-to-validate-email-address/

public boolean isValidEmailAddress(String emailAddress){
String expression="^[\\w\\-]([\\.\\w])+[\\w]+@([\\w\\-]+\\.)+[A-Z]{2,4}$";
CharSequence inputStr = emailAddress;
Pattern pattern = Pattern.compile(expression,Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher(inputStr);
return matcher.matches();
}