public static boolean checkEmail(String value) {
		if ( value == null || value.equals("") ) {
			return true;
		}
		if ( value.matches("^[a-zA-Z0-9-_][a-zA-Z0-9-._]*@[a-zA-Z0-9-._]+[a-zA-Z0-9]$") == false ) {
			return false;
		}
		return true;
	}