郵箱正則表示式
public static boolean isEmail(String email){
String pattern =
"^[a-zA-Z][\\w\\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\\w\\.-]*[a-zA-Z0-9]\\.[a-zA-Z][a-ZA-Z\\.]*[a-zA-Z]$";
Pattern p = Pattern.compile(pattern);
Matcher m = p.matcher(email);
return m.matches();
}