Java中有哪些好的电子邮件地址验证库?有没有共享验证器的替代品?
Apache Commons通常被认为是一个可靠的项目。但是请记住，如果你想确保它是一个真实的电子邮件，并且所有者希望它在你的网站上使用，你仍然需要发送一封验证邮件到这个地址。
编辑:有一个错误，它对域的限制太大，导致它不接受来自新tld的有效电子邮件。 此错误已于03/Jan/15 02:48在commons-validator版本1.4.1中解决
编辑:有一个错误，它对域的限制太大，导致它不接受来自新tld的有效电子邮件。
此错误已于03/Jan/15 02:48在commons-validator版本1.4.1中解决
您想验证什么?电子邮件地址?
只能检查电子邮件地址的格式是否符合要求。参见标准:RFC2822。最好的方法是使用正则表达式。如果不发一封邮件，你永远不会知道是否真的存在。
我检查了公共验证器。它包含一个org.apache.commons.validator.EmailValidator类。看起来是个不错的起点。
如果你想要验证一个电子邮件地址是否有效，那么VRFY将为你提供一些方法。我发现它对验证内部网地址(即内部站点的电子邮件地址)很有用。然而，它对互联网邮件服务器的用处不大(请参阅本页顶部的警告)
Les Hazlewood使用Java正则表达式编写了一个非常完整的符合RFC 2822的电子邮件验证器类。你可以在http://www.leshazlewood.com/?p=23找到它。然而，它的彻底性(或Java RE实现)导致效率低下——阅读关于长地址解析时间的注释。
你可能还想检查长度——电子邮件的长度不超过254个字符。我使用apache commons验证器，它不检查这个。
当前的Apache Commons Validator版本是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，它来自一个退役的雅加达ORO项目。
使用官方Java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; }
我移植了Zend_Validator_Email中的一些代码:
@FacesValidator("emailValidator") public class EmailAddressValidator implements Validator { private String localPart; private String hostName; private boolean domain = true; Locale locale; ResourceBundle bundle; private List<FacesMessage> messages = new ArrayList<FacesMessage>(); private HostnameValidator hostnameValidator; @Override public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException { setOptions(component); String email = (String) value; boolean result = true; Pattern pattern = Pattern.compile("^(.+)@([^@]+[^.])$"); Matcher matcher = pattern.matcher(email); locale = context.getViewRoot().getLocale(); bundle = ResourceBundle.getBundle("com.myapp.resources.validationMessages", locale); boolean length = true; boolean local = true; if (matcher.find()) { localPart = matcher.group(1); hostName = matcher.group(2); if (localPart.length() > 64 || hostName.length() > 255) { length = false; addMessage("enterValidEmail", "email.AddressLengthExceeded"); } if (domain == true) { hostnameValidator = new HostnameValidator(); hostnameValidator.validate(context, component, hostName); } local = validateLocalPart(); if (local && length) { result = true; } else { result = false; } } else { result = false; addMessage("enterValidEmail", "invalidEmailAddress"); } if (result == false) { throw new ValidatorException(messages); } } private boolean validateLocalPart() { // First try to match the local part on the common dot-atom format boolean result = false; // Dot-atom characters are: 1*atext *("." 1*atext) // atext: ALPHA / DIGIT / and "!", "#", "$", "%", "&", "'", "*", // "+", "-", "/", "=", "?", "^", "_", "`", "{", "|", "}", "~" String atext = "a-zA-Z0-9\\u0021\\u0023\\u0024\\u0025\\u0026\\u0027\\u002a" + "\\u002b\\u002d\\u002f\\u003d\\u003f\\u005e\\u005f\\u0060\\u007b" + "\\u007c\\u007d\\u007e"; Pattern regex = Pattern.compile("^["+atext+"]+(\\u002e+["+atext+"]+)*$"); Matcher matcher = regex.matcher(localPart); if (matcher.find()) { result = true; } else { // Try quoted string format // Quoted-string characters are: DQUOTE *([FWS] qtext/quoted-pair) [FWS] DQUOTE // qtext: Non white space controls, and the rest of the US-ASCII characters not // including "\" or the quote character String noWsCtl = "\\u0001-\\u0008\\u000b\\u000c\\u000e-\\u001f\\u007f"; String qText = noWsCtl + "\\u0021\\u0023-\\u005b\\u005d-\\u007e"; String ws = "\\u0020\\u0009"; regex = Pattern.compile("^\\u0022(["+ws+qText+"])*["+ws+"]?\\u0022$"); matcher = regex.matcher(localPart); if (matcher.find()) { result = true; } else { addMessage("enterValidEmail", "email.AddressDotAtom"); addMessage("enterValidEmail", "email.AddressQuotedString"); addMessage("enterValidEmail", "email.AddressInvalidLocalPart"); } } return result; } private void addMessage(String detail, String summary) { String detailMsg = bundle.getString(detail); String summaryMsg = bundle.getString(summary); messages.add(new FacesMessage(FacesMessage.SEVERITY_ERROR, summaryMsg, detailMsg)); } private void setOptions(UIComponent component) { Boolean domainOption = Boolean.valueOf((String) component.getAttributes().get("domain")); //domain = (domainOption == null) ? true : domainOption.booleanValue(); } }
使用主机名验证器如下所示:
@FacesValidator("hostNameValidator") public class HostnameValidator implements Validator { private Locale locale; private ResourceBundle bundle; private List<FacesMessage> messages; private boolean checkTld = true; private boolean allowLocal = false; private boolean allowDNS = true; private String tld; private String[] validTlds = {"ac", "ad", "ae", "aero", "af", "ag", "ai", "al", "am", "an", "ao", "aq", "ar", "arpa", "as", "asia", "at", "au", "aw", "ax", "az", "ba", "bb", "bd", "be", "bf", "bg", "bh", "bi", "biz", "bj", "bm", "bn", "bo", "br", "bs", "bt", "bv", "bw", "by", "bz", "ca", "cat", "cc", "cd", "cf", "cg", "ch", "ci", "ck", "cl", "cm", "cn", "co", "com", "coop", "cr", "cu", "cv", "cx", "cy", "cz", "de", "dj", "dk", "dm", "do", "dz", "ec", "edu", "ee", "eg", "er", "es", "et", "eu", "fi", "fj", "fk", "fm", "fo", "fr", "ga", "gb", "gd", "ge", "gf", "gg", "gh", "gi", "gl", "gm", "gn", "gov", "gp", "gq", "gr", "gs", "gt", "gu", "gw", "gy", "hk", "hm", "hn", "hr", "ht", "hu", "id", "ie", "il", "im", "in", "info", "int", "io", "iq", "ir", "is", "it", "je", "jm", "jo", "jobs", "jp", "ke", "kg", "kh", "ki", "km", "kn", "kp", "kr", "kw", "ky", "kz", "la", "lb", "lc", "li", "lk", "lr", "ls", "lt", "lu", "lv", "ly", "ma", "mc", "md", "me", "mg", "mh", "mil", "mk", "ml", "mm", "mn", "mo", "mobi", "mp", "mq", "mr", "ms", "mt", "mu", "museum", "mv", "mw", "mx", "my", "mz", "na", "name", "nc", "ne", "net", "nf", "ng", "ni", "nl", "no", "np", "nr", "nu", "nz", "om", "org", "pa", "pe", "pf", "pg", "ph", "pk", "pl", "pm", "pn", "pr", "pro", "ps", "pt", "pw", "py", "qa", "re", "ro", "rs", "ru", "rw", "sa", "sb", "sc", "sd", "se", "sg", "sh", "si", "sj", "sk", "sl", "sm", "sn", "so", "sr", "st", "su", "sv", "sy", "sz", "tc", "td", "tel", "tf", "tg", "th", "tj", "tk", "tl", "tm", "tn", "to", "tp", "tr", "travel", "tt", "tv", "tw", "tz", "ua", "ug", "uk", "um", "us", "uy", "uz", "va", "vc", "ve", "vg", "vi", "vn", "vu", "wf", "ws", "ye", "yt", "yu", "za", "zm", "zw"}; private Map<String, Map<Integer, Integer>> idnLength; private void init() { Map<Integer, Integer> biz = new HashMap<Integer, Integer>(); biz.put(5, 17); biz.put(11, 15); biz.put(12, 20); Map<Integer, Integer> cn = new HashMap<Integer, Integer>(); cn.put(1, 20); Map<Integer, Integer> com = new HashMap<Integer, Integer>(); com.put(3, 17); com.put(5, 20); Map<Integer, Integer> hk = new HashMap<Integer, Integer>(); hk.put(1, 15); Map<Integer, Integer> info = new HashMap<Integer, Integer>(); info.put(4, 17); Map<Integer, Integer> kr = new HashMap<Integer, Integer>(); kr.put(1, 17); Map<Integer, Integer> net = new HashMap<Integer, Integer>(); net.put(3, 17); net.put(5, 20); Map<Integer, Integer> org = new HashMap<Integer, Integer>(); org.put(6, 17); Map<Integer, Integer> tw = new HashMap<Integer, Integer>(); tw.put(1, 20); Map<Integer, Integer> idn1 = new HashMap<Integer, Integer>(); idn1.put(1, 20); Map<Integer, Integer> idn2 = new HashMap<Integer, Integer>(); idn2.put(1, 20); Map<Integer, Integer> idn3 = new HashMap<Integer, Integer>(); idn3.put(1, 20); Map<Integer, Integer> idn4 = new HashMap<Integer, Integer>(); idn4.put(1, 20); idnLength = new HashMap<String, Map<Integer, Integer>>(); idnLength.put("BIZ", biz); idnLength.put("CN", cn); idnLength.put("COM", com); idnLength.put("HK", hk); idnLength.put("INFO", info); idnLength.put("KR", kr); idnLength.put("NET", net); idnLength.put("ORG", org); idnLength.put("TW", tw); idnLength.put("ایران", idn1); idnLength.put("中国", idn2); idnLength.put("公司", idn3); idnLength.put("网络", idn4); messages = new ArrayList<FacesMessage>(); } public HostnameValidator() { init(); } @Override public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException { String hostName = (String) value; locale = context.getViewRoot().getLocale(); bundle = ResourceBundle.getBundle("com.myapp.resources.validationMessages", locale); Pattern ipPattern = Pattern.compile("^[0-9a-f:\\.]*$", Pattern.CASE_INSENSITIVE); Matcher ipMatcher = ipPattern.matcher(hostName); if (ipMatcher.find()) { addMessage("hostname.IpAddressNotAllowed"); throw new ValidatorException(messages); } boolean result = false; // removes last dot (.) from hostname hostName = hostName.replaceAll("(\\.)+$", ""); String[] domainParts = hostName.split("\\."); boolean status = false; // Check input against DNS hostname schema if ((domainParts.length > 1) && (hostName.length() > 4) && (hostName.length() < 255)) { status = false; dowhile: do { // First check TLD int lastIndex = domainParts.length - 1; String domainEnding = domainParts[lastIndex]; Pattern tldRegex = Pattern.compile("([^.]{2,10})", Pattern.CASE_INSENSITIVE); Matcher tldMatcher = tldRegex.matcher(domainEnding); if (tldMatcher.find() || domainEnding.equals("ایران") || domainEnding.equals("中国") || domainEnding.equals("公司") || domainEnding.equals("网络")) { // Hostname characters are: *(label dot)(label dot label); max 254 chars // label: id-prefix [*ldh{61} id-prefix]; max 63 chars // id-prefix: alpha / digit // ldh: alpha / digit / dash // Match TLD against known list tld = (String) tldMatcher.group(1).toLowerCase().trim(); if (checkTld == true) { boolean foundTld = false; for (int i = 0; i < validTlds.length; i++) { if (tld.equals(validTlds[i])) { foundTld = true; } } if (foundTld == false) { status = false; addMessage("hostname.UnknownTld"); break dowhile; } } /** * Match against IDN hostnames * Note: Keep label regex short to avoid issues with long patterns when matching IDN hostnames */ List<String> regexChars = getIdnRegexChars(); // Check each hostname part int check = 0; for (String domainPart : domainParts) { // Decode Punycode domainnames to IDN if (domainPart.indexOf("xn--") == 0) { domainPart = decodePunycode(domainPart.substring(4)); } // Check dash (-) does not start, end or appear in 3rd and 4th positions if (domainPart.indexOf("-") == 0 || (domainPart.length() > 2 && domainPart.indexOf("-", 2) == 2 && domainPart.indexOf("-", 3) == 3) || (domainPart.indexOf("-") == (domainPart.length() - 1))) { status = false; addMessage("hostname.DashCharacter"); break dowhile; } // Check each domain part boolean checked = false; for (int key = 0; key < regexChars.size(); key++) { String regexChar = regexChars.get(key); Pattern regex = Pattern.compile(regexChar); Matcher regexMatcher = regex.matcher(domainPart); status = regexMatcher.find(); if (status) { int length = 63; if (idnLength.containsKey(tld.toUpperCase()) && idnLength.get(tld.toUpperCase()).containsKey(key)) { length = idnLength.get(tld.toUpperCase()).get(key); } int utf8Length; try { utf8Length = domainPart.getBytes("UTF8").length; if (utf8Length > length) { addMessage("hostname.InvalidHostname"); } else { checked = true; break; } } catch (UnsupportedEncodingException ex) { Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex); } } } if (checked) { ++check; } } // If one of the labels doesn't match, the hostname is invalid if (check != domainParts.length) { status = false; addMessage("hostname.InvalidHostnameSchema"); } } else { // Hostname not long enough status = false; addMessage("hostname.UndecipherableTld"); } } while (false); if (status == true && allowDNS) { result = true; } } else if (allowDNS == true) { addMessage("hostname.InvalidHostname"); throw new ValidatorException(messages); } // Check input against local network name schema; Pattern regexLocal = Pattern.compile("^(([a-zA-Z0-9\\x2d]{1,63}\\x2e)*[a-zA-Z0-9\\x2d]{1,63}){1,254}$", Pattern.CASE_INSENSITIVE); boolean checkLocal = regexLocal.matcher(hostName).find(); if (allowLocal && !status) { if (checkLocal) { result = true; } else { // If the input does not pass as a local network name, add a message result = false; addMessage("hostname.InvalidLocalName"); } } // If local network names are not allowed, add a message if (checkLocal && !allowLocal && !status) { result = false; addMessage("hostname.LocalNameNotAllowed"); } if (result == false) { throw new ValidatorException(messages); } } private void addMessage(String msg) { String bundlMsg = bundle.getString(msg); messages.add(new FacesMessage(FacesMessage.SEVERITY_ERROR, bundlMsg, bundlMsg)); } /** * Returns a list of regex patterns for the matched TLD * @param tld * @return */ private List<String> getIdnRegexChars() { List<String> regexChars = new ArrayList<String>(); regexChars.add("^[a-z0-9\\x2d]{1,63}$"); Document doc = null; DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); factory.setNamespaceAware(true); try { InputStream validIdns = getClass().getClassLoader().getResourceAsStream("com/myapp/resources/validIDNs_1.xml"); DocumentBuilder builder = factory.newDocumentBuilder(); doc = builder.parse(validIdns); doc.getDocumentElement().normalize(); } catch (SAXException ex) { Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex); } catch (IOException ex) { Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex); } catch (ParserConfigurationException ex) { Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex); } // prepare XPath XPath xpath = XPathFactory.newInstance().newXPath(); NodeList nodes = null; String xpathRoute = "//idn[tld=\'" + tld.toUpperCase() + "\']/pattern/text()"; try { XPathExpression expr; expr = xpath.compile(xpathRoute); Object res = expr.evaluate(doc, XPathConstants.NODESET); nodes = (NodeList) res; } catch (XPathExpressionException ex) { Logger.getLogger(HostnameValidator.class.getName()).log(Level.SEVERE, null, ex); } for (int i = 0; i < nodes.getLength(); i++) { regexChars.add(nodes.item(i).getNodeValue()); } return regexChars; } /** * Decode Punycode string * @param encoded * @return */ private String decodePunycode(String encoded) { Pattern regex = Pattern.compile("([^a-z0-9\\x2d]{1,10})", Pattern.CASE_INSENSITIVE); Matcher matcher = regex.matcher(encoded); boolean found = matcher.find(); if (encoded.isEmpty() || found) { // no punycode encoded string, return as is addMessage("hostname.CannotDecodePunycode"); throw new ValidatorException(messages); } int separator = encoded.lastIndexOf("-"); List<Integer> decoded = new ArrayList<Integer>(); if (separator > 0) { for (int x = 0; x < separator; ++x) { decoded.add((int) encoded.charAt(x)); } } else { addMessage("hostname.CannotDecodePunycode"); throw new ValidatorException(messages); } int lengthd = decoded.size(); int lengthe = encoded.length(); // decoding boolean init = true; int base = 72; int index = 0; int ch = 0x80; int indexeStart = (separator == 1) ? (separator + 1) : 0; for (int indexe = indexeStart; indexe < lengthe; ++lengthd) { int oldIndex = index; int pos = 1; for (int key = 36; true; key += 36) { int hex = (int) encoded.charAt(indexe++); int digit = (hex - 48 < 10) ? hex - 22 : ((hex - 65 < 26) ? hex - 65 : ((hex - 97 < 26) ? hex - 97 : 36)); index += digit * pos; int tag = (key <= base) ? 1 : ((key >= base + 26) ? 26 : (key - base)); if (digit < tag) { break; } pos = (int) (pos * (36 - tag)); } int delta = (int) (init ? ((index - oldIndex) / 700) : ((index - oldIndex) / 2)); delta += (int) (delta / (lengthd + 1)); int key; for (key = 0; delta > 910; key += 36) { delta = (int) (delta / 35); } base = (int) (key + 36 * delta / (delta + 38)); init = false; ch += (int) (index / (lengthd + 1)); index %= (lengthd + 1); if (lengthd > 0) { for (int i = lengthd; i > index; i--) { decoded.set(i, decoded.get(i - 1)); } } decoded.set(index++, ch); } // convert decoded ucs4 to utf8 string StringBuilder sb = new StringBuilder(); for (int i = 0; i < decoded.size(); i++) { int value = decoded.get(i); if (value < 128) { sb.append((char) value); } else if (value < (1 << 11)) { sb.append((char) (192 + (value >> 6))); sb.append((char) (128 + (value & 63))); } else if (value < (1 << 16)) { sb.append((char) (224 + (value >> 12))); sb.append((char) (128 + ((value >> 6) & 63))); sb.append((char) (128 + (value & 63))); } else if (value < (1 << 21)) { sb.append((char) (240 + (value >> 18))); sb.append((char) (128 + ((value >> 12) & 63))); sb.append((char) (128 + ((value >> 6) & 63))); sb.append((char) (128 + (value & 63))); } else { addMessage("hostname.CannotDecodePunycode"); throw new ValidatorException(messages); } } return sb.toString(); } /** * Eliminates empty values from input array * @param data * @return */ private String[] verifyArray(String[] data) { List<String> result = new ArrayList<String>(); for (String s : data) { if (!s.equals("")) { result.add(s); } } return result.toArray(new String[result.size()]); } }
和一个valididdns .xml，带有不同tld的regex模式(太大了，不能包括:)
<idnlist> <idn> <tld>AC</tld> <pattern>^[\u002d0-9a-zà-öø-ÿāăąćĉċčďđēėęěĝġģĥħīįĵķĺļľŀłńņňŋőœŕŗřśŝşšţťŧūŭůűųŵŷźżž]{1,63}$</pattern> </idn> <idn> <tld>AR</tld> <pattern>^[\u002d0-9a-zà-ãç-êìíñ-õü]{1,63}$</pattern> </idn> <idn> <tld>AS</tld> <pattern>/^[\u002d0-9a-zà-öø-ÿāăąćĉċčďđēĕėęěĝğġģĥħĩīĭįıĵķĸĺļľłńņňŋōŏőœŕŗřśŝşšţťŧũūŭůűųŵŷźż]{1,63}$</pattern> </idn> <idn> <tld>AT</tld> <pattern>/^[\u002d0-9a-zà-öø-ÿœšž]{1,63}$</pattern> </idn> <idn> <tld>BIZ</tld> <pattern>^[\u002d0-9a-zäåæéöøü]{1,63}$</pattern> <pattern>^[\u002d0-9a-záéíñóúü]{1,63}$</pattern> <pattern>^[\u002d0-9a-záéíóöúüőű]{1,63}$</pattern> </id> </idlist>
我在这个地址上维护了一个类:http://lacinato.com/cm/software/emailrelated/emailaddress
它基于Les Hazlewood的类，但有许多改进并修复了一些错误。Apache许可证。
我相信它是Java中功能最强大的电子邮件解析器，我还没有在任何语言中看到比它更强大的，尽管可能会有一个。它不是lexer风格的解析器，而是使用一些复杂的java regex，因此效率不高，但我的公司已经用它解析了超过100亿个真实地址:它在高性能情况下当然是有用的。也许一年一次，它会碰到一个地址，导致正则表达式堆栈溢出(适当)，但这些是垃圾地址，有成百上千个字符长，有很多很多引号和括号之类的。
RFC 2822和相关的规范在电子邮件地址方面是非常宽松的，所以这样的类对于大多数用途来说是多余的。例如，以下是一个合法的地址，根据规范，空格和所有:
"<bob \" (here) " < (hi there) "bob(the man)smith" (hi) @ (there) example.com (hello) > (again)
没有邮件服务器允许这样做，但是这个类可以解析它(并将其重写为可用的形式)。
我们发现现有的Java电子邮件解析器选项不够持久(也就是说，它们都不能解析一些有效地址)，因此创建了这个类。
该代码有良好的文档记录，并且有许多易于更改的选项来允许或禁止某些电子邮件表单。它还提供了许多方法来访问地址的某些部分(左侧、右侧、个人姓名、注释等)，解析/验证邮箱列表头，解析/验证返回路径(在头中是唯一的)，等等。
编写的代码有一个javamail依赖项，但是如果您不想要它提供的次要功能，那么很容易删除它。
回答迟了，但我觉得简单而有价值:
public boolean isValidEmailAddress(String email) { String ePattern = "^[a-zA-Z0-9.!#$%&'*+/=?^_`{|}~-]+@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\])|(([a-zA-Z\\-0-9]+\\.)+[a-zA-Z]{2,}))$"; java.util.regex.Pattern p = java.util.regex.Pattern.compile(ePattern); java.util.regex.Matcher m = p.matcher(email); return m.matches(); }
测试用例:
出于生产目的，域名验证应该在网络上执行。
public class Validations { private Pattern regexPattern; private Matcher regMatcher; public String validateEmailAddress(String emailAddress) { regexPattern = Pattern.compile("^[(a-zA-Z-0-9-\\_\\+\\.)]+@[(a-z-A-z)]+\\.[(a-zA-z)]{2,3}$"); regMatcher = regexPattern.matcher(emailAddress); if(regMatcher.matches()) { return "Valid Email Address"; } else { return "Invalid Email Address"; } } public String validateMobileNumber(String mobileNumber) { regexPattern = Pattern.compile("^\\+[0-9]{2,3}+-[0-9]{10}$"); regMatcher = regexPattern.matcher(mobileNumber); if(regMatcher.matches()) { return "Valid Mobile Number"; } else { return "Invalid Mobile Number"; } } public static void main(String[] args) { String emailAddress = "suryaprakash.pisay@gmail.com"; String mobileNumber = "+91-9986571622"; Validations validations = new Validations(); System.out.println(validations.validateEmailAddress(emailAddress)); System.out.println(validations.validateMobileNumber(mobileNumber)); } }
似乎没有任何完美的库或方法可以自己做到这一点，除非您必须有时间向电子邮件地址发送电子邮件并等待回复(尽管这可能不是一个选项)。我最终使用了一个建议，从这里http://blog.logichigh.com/2010/09/02/validating-an-e-mail-address/和调整代码，使它可以在Java中工作。
public static boolean isValidEmailAddress(String email) { boolean stricterFilter = true; String stricterFilterString = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}"; String laxString = ".+@.+\\.[A-Za-z]{2}[A-Za-z]*"; String emailRegex = stricterFilter ? stricterFilterString : laxString; java.util.regex.Pattern p = java.util.regex.Pattern.compile(emailRegex); java.util.regex.Matcher m = p.matcher(email); return m.matches(); }
我只是想知道为什么没有人从Hibernate验证器的附加约束中想出@Email。验证器本身是EmailValidator。
@Email
EmailValidator
Pattern pattern = Pattern.compile("^.+@.+\\..+$"); Matcher matcher = pattern.matcher(email);
可以像其他答案中提到的那样使用Apache Commons验证器。
pom.xml:
<dependency> <groupId>commons-validator</groupId> <artifactId>commons-validator</artifactId> <version>1.4.1</version> </dependency>
build.gradle:
compile 'commons-validator:commons-validator:1.4.1'
导入:
import org.apache.commons.validator.routines.EmailValidator;
代码:
String email = "myName@example.com"; boolean valid = EmailValidator.getInstance().isValid(email);
并允许本地地址
boolean allowLocal = true; boolean valid = EmailValidator.getInstance(allowLocal).isValid(email);
这是最好的方法:
public static boolean isValidEmail(String enteredEmail){ String EMAIL_REGIX = "^[\\\\w!#$%&’*+/=?`{|}~^-]+(?:\\\\.[\\\\w!#$%&’*+/=?`{|}~^-]+)*@(?:[a-zA-Z0-9-]+\\\\.)+[a-zA-Z]{2,6}$"; Pattern pattern = Pattern.compile(EMAIL_REGIX); Matcher matcher = pattern.matcher(enteredEmail); return ((!enteredEmail.isEmpty()) && (enteredEmail!=null) && (matcher.matches())); }
http://www.rfc-editor.org/rfc/rfc5322.txt
下面是我的实用方法，我只需要使用RFC中允许的字符合理地区分blah@domain地址。地址必须事先转换为小写。
public class EmailAddressValidator { private static final String domainChars = "a-z0-9\\-"; private static final String atomChars = "a-z0-9\\Q!#$%&'*+-/=?^_`{|}~\\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(); } }
另一种选择是使用Hibernate电子邮件验证器，使用注释@Email或以编程方式使用验证器类，例如:
import org.hibernate.validator.internal.constraintvalidators.hv.EmailValidator; class Validator { // code private boolean isValidEmail(String email) { EmailValidator emailValidator = new EmailValidator(); return emailValidator.isValid(email, null); } }
虽然有很多替代Apache commons的方法，但它们的实现充其量是基本的(就像Apache commons的实现本身)，甚至在其他情况下是完全错误的。
我也会远离所谓的简单的“非限制性”正则表达式;没有这样的事。例如，@允许多次使用取决于上下文，你如何知道需要的一个在那里?简单的正则表达式无法理解它，即使电子邮件应该是有效的。任何更复杂的都会变成容易出错的，甚至包含隐藏的性能杀手。你将如何维护这这样的东西?
我所知道的唯一全面的符合RFC的基于正则表达式的验证器是email-rfc2822-validator，它的“精炼”正则表达式适当地命名为Dragons.java。虽然它只支持较旧的rfc - 2822规范，但已经足够满足现代需求(RFC-5322 < em > < / em >更新已经超出日常使用范围)。
但是really what you want是一个lexer根据RFC语法正确地解析字符串并将其分解为组件结构。EmailValidator4J在这方面似乎很有前途，但仍然年轻和有限。
另一种选择是使用webservice，比如Mailgun经过战斗测试的确认网络服务或Mailboxlayer API(只取第一个谷歌结果)。它不是严格的RFC兼容，但是对于现代需求来说已经足够好了。
