当前的Apache Commons Validator版本为1.3.1。

进行验证的类是org.apache.commons.validator.EmailValidator。它导入了org.apache.oro.text.perl。Perl5Util来自一个退役的雅加达ORO项目。

BTW, I found that there is a 1.4 version, here are the API docs. On the site it says: "Last Published: 05 March 2008 | Version: 1.4-SNAPSHOT", but that's not final. Only way to build yourself (but this is a snapshot, not RELEASE) and use, or download from here. This means 1.4 has not been made final for three years (2008-2011). This is not in Apache's style. I'm looking for a better option, but didn't find one that is very adopted. I want to use something that is well tested, don't want to hit any bugs.

我只是想知道为什么没有人从Hibernate Validator的附加约束中想出@Email。验证器本身就是EmailValidator。

我在这个地址上维护了一个类:http://lacinato.com/cm/software/emailrelated/emailaddress

它基于Les Hazlewood的类，但有许多改进并修复了一些错误。Apache许可证。

I believe it is the most capable email parser in Java, and I have yet to see one more capable in any language, though there may be one out there. It's not a lexer-style parser, but uses some complicated java regex, and thus is not as efficient as it could be, but my company has parsed well over 10 billion real-world addresses with it: it's certainly usable in a high-performance situation. Maybe once a year it'll hit an address that causes a regex stack overflow (appropriately), but these are spam addresses which are hundreds or thousands of characters long with many many quotes and parenthesis and the like.

RFC 2822和相关规范在电子邮件地址方面是非常宽松的，所以这样的类对于大多数用途来说是多余的。例如，以下是一个合法的地址，根据规范，空格和所有:

"<bob \" (here) " < (hi there) "bob(the man)smith" (hi) @ (there) example.com (hello) > (again)

没有邮件服务器允许这样做，但是这个类可以解析它(并将其重写为可用的形式)。

我们发现现有的Java电子邮件解析器选项不够持久(也就是说，它们都不能解析一些有效地址)，因此创建了这个类。

该代码有良好的文档记录，并且有许多易于更改的选项来允许或禁止某些电子邮件表单。它还提供了许多方法来访问地址的某些部分(左侧、右侧、个人姓名、注释等)，解析/验证邮箱列表头，解析/验证返回路径(在头中是唯一的)，等等。

编写的代码有一个javamail依赖项，但是如果您不想要它提供的次要功能，那么很容易删除它。

使用官方的java电子邮件包是最简单的:

public static boolean isValidEmailAddress(String email) {
   boolean result = true;
   try {
      InternetAddress emailAddr = new InternetAddress(email);
      emailAddr.validate();
   } catch (AddressException ex) {
      result = false;
   }
   return result;
}

下面是我的实用方法，我只需要使用RFC中允许的字符合理地区分blah@domain地址。地址必须事先转换为小写。

public class EmailAddressValidator {

    private static final String domainChars = "a-z0-9\\-";
    private static final String atomChars = "a-z0-9\\Q!#$%&'*+-/=?^_`{|}~\\E";
    private static final String emailRegex = "^" + dot(atomChars) + "@" + dot(domainChars) + "$";
    private static final Pattern emailPattern = Pattern.compile(emailRegex);

    private static String dot(String chars) {
        return "[" + chars + "]+(?:\\.[" + chars + "]+)*";
    }

    public static boolean isValidEmailAddress(String address) {
        return address != null && emailPattern.matcher(address).matches();
    }

}

当前的Apache Commons Validator版本为1.3.1。

进行验证的类是org.apache.commons.validator.EmailValidator。它导入了org.apache.oro.text.perl。Perl5Util来自一个退役的雅加达ORO项目。

BTW, I found that there is a 1.4 version, here are the API docs. On the site it says: "Last Published: 05 March 2008 | Version: 1.4-SNAPSHOT", but that's not final. Only way to build yourself (but this is a snapshot, not RELEASE) and use, or download from here. This means 1.4 has not been made final for three years (2008-2011). This is not in Apache's style. I'm looking for a better option, but didn't find one that is very adopted. I want to use something that is well tested, don't want to hit any bugs.