public class EmailPassDetectorRegular {

    public EmailPassDetectorRegular(){}

    public String handle(String str){

        if(str.matches("^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\\\\.[A-Za-z]{2,6}+[;:]+(.*)$"))
            return str;
        else
            return null;
    }
}