我用使用RegexBuddy使用正则表达式时。 从它的图书馆我复制了正则表达式匹配的URL。 我内使用RegexBuddy测试成功。 然而，当我把它抄了如Java String风味和粘贴成Java代码，这是行不通的。 下面的类打印false ：
public class RegexFoo {
public static void main(String[] args) {
String regex = "\\b(https?|ftp|file)://[-A-Z0-9+&@#/%?=~_|!:,.;]*[-A-Z0-9+&@#/%=~_|]";
String text = "http://google.com";
System.out.println(IsMatch(text,regex));
}
private static boolean IsMatch(String s, String pattern) {
try {
Pattern patt = Pattern.compile(pattern);
Matcher matcher = patt.matcher(s);
return matcher.matches();
} catch (RuntimeException e) {
return false;
}
}
}
有谁知道我做错了吗？
Answer 1:
试试下面的正则表达式的字符串，而不是。 您的测试可能是在区分大小写的方式进行。 我已经添加了小写的阿尔法以及适当的字符串开头的占位符。
String regex = "^(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]";
这工作太：
String regex = "\\b(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]";
注意：
String regex = "<\\b(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]>"; // matches <http://google.com>
String regex = "<^(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]>"; // does not match <http://google.com>
Answer 2:
现在做到这一点的最好办法是：
android.util.Patterns.WEB_URL.matcher(linkUrl).matches();
编辑：规范Patterns从https://github.com/android/platform_frameworks_base/blob/master/core/java/android/util/Patterns.java ：
/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.util;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* Commonly used regular expression patterns.
*/
public class Patterns {
/**
* Regular expression to match all IANA top-level domains.
* List accurate as of 2011/07/18. List taken from:
* http://data.iana.org/TLD/tlds-alpha-by-domain.txt
* This pattern is auto-generated by frameworks/ex/common/tools/make-iana-tld-pattern.py
*
* @deprecated Due to the recent profileration of gTLDs, this API is
* expected to become out-of-date very quickly. Therefore it is now
* deprecated.
*/
@Deprecated
public static final String TOP_LEVEL_DOMAIN_STR =
"((aero|arpa|asia|a[cdefgilmnoqrstuwxz])"
+ "|(biz|b[abdefghijmnorstvwyz])"
+ "|(cat|com|coop|c[acdfghiklmnoruvxyz])"
+ "|d[ejkmoz]"
+ "|(edu|e[cegrstu])"
+ "|f[ijkmor]"
+ "|(gov|g[abdefghilmnpqrstuwy])"
+ "|h[kmnrtu]"
+ "|(info|int|i[delmnoqrst])"
+ "|(jobs|j[emop])"
+ "|k[eghimnprwyz]"
+ "|l[abcikrstuvy]"
+ "|(mil|mobi|museum|m[acdeghklmnopqrstuvwxyz])"
+ "|(name|net|n[acefgilopruz])"
+ "|(org|om)"
+ "|(pro|p[aefghklmnrstwy])"
+ "|qa"
+ "|r[eosuw]"
+ "|s[abcdeghijklmnortuvyz]"
+ "|(tel|travel|t[cdfghjklmnoprtvwz])"
+ "|u[agksyz]"
+ "|v[aceginu]"
+ "|w[fs]"
+ "|(\u03b4\u03bf\u03ba\u03b9\u03bc\u03ae|\u0438\u0441\u043f\u044b\u0442\u0430\u043d\u0438\u0435|\u0440\u0444|\u0441\u0440\u0431|\u05d8\u05e2\u05e1\u05d8|\u0622\u0632\u0645\u0627\u06cc\u0634\u06cc|\u0625\u062e\u062a\u0628\u0627\u0631|\u0627\u0644\u0627\u0631\u062f\u0646|\u0627\u0644\u062c\u0632\u0627\u0626\u0631|\u0627\u0644\u0633\u0639\u0648\u062f\u064a\u0629|\u0627\u0644\u0645\u063a\u0631\u0628|\u0627\u0645\u0627\u0631\u0627\u062a|\u0628\u06be\u0627\u0631\u062a|\u062a\u0648\u0646\u0633|\u0633\u0648\u0631\u064a\u0629|\u0641\u0644\u0633\u0637\u064a\u0646|\u0642\u0637\u0631|\u0645\u0635\u0631|\u092a\u0930\u0940\u0915\u094d\u0937\u093e|\u092d\u093e\u0930\u0924|\u09ad\u09be\u09b0\u09a4|\u0a2d\u0a3e\u0a30\u0a24|\u0aad\u0abe\u0ab0\u0aa4|\u0b87\u0ba8\u0bcd\u0ba4\u0bbf\u0baf\u0bbe|\u0b87\u0bb2\u0b99\u0bcd\u0b95\u0bc8|\u0b9a\u0bbf\u0b99\u0bcd\u0b95\u0baa\u0bcd\u0baa\u0bc2\u0bb0\u0bcd|\u0baa\u0bb0\u0bbf\u0b9f\u0bcd\u0b9a\u0bc8|\u0c2d\u0c3e\u0c30\u0c24\u0c4d|\u0dbd\u0d82\u0d9a\u0dcf|\u0e44\u0e17\u0e22|\u30c6\u30b9\u30c8|\u4e2d\u56fd|\u4e2d\u570b|\u53f0\u6e7e|\u53f0\u7063|\u65b0\u52a0\u5761|\u6d4b\u8bd5|\u6e2c\u8a66|\u9999\u6e2f|\ud14c\uc2a4\ud2b8|\ud55c\uad6d|xn\\-\\-0zwm56d|xn\\-\\-11b5bs3a9aj6g|xn\\-\\-3e0b707e|xn\\-\\-45brj9c|xn\\-\\-80akhbyknj4f|xn\\-\\-90a3ac|xn\\-\\-9t4b11yi5a|xn\\-\\-clchc0ea0b2g2a9gcd|xn\\-\\-deba0ad|xn\\-\\-fiqs8s|xn\\-\\-fiqz9s|xn\\-\\-fpcrj9c3d|xn\\-\\-fzc2c9e2c|xn\\-\\-g6w251d|xn\\-\\-gecrj9c|xn\\-\\-h2brj9c|xn\\-\\-hgbk6aj7f53bba|xn\\-\\-hlcj6aya9esc7a|xn\\-\\-j6w193g|xn\\-\\-jxalpdlp|xn\\-\\-kgbechtv|xn\\-\\-kprw13d|xn\\-\\-kpry57d|xn\\-\\-lgbbat1ad8j|xn\\-\\-mgbaam7a8h|xn\\-\\-mgbayh7gpa|xn\\-\\-mgbbh1a71e|xn\\-\\-mgbc0a9azcg|xn\\-\\-mgberp4a5d4ar|xn\\-\\-o3cw4h|xn\\-\\-ogbpf8fl|xn\\-\\-p1ai|xn\\-\\-pgbs0dh|xn\\-\\-s9brj9c|xn\\-\\-wgbh1c|xn\\-\\-wgbl6a|xn\\-\\-xkc2al3hye2a|xn\\-\\-xkc2dl3a5ee0h|xn\\-\\-yfro4i67o|xn\\-\\-ygbi2ammx|xn\\-\\-zckzah|xxx)"
+ "|y[et]"
+ "|z[amw])";
/**
* Regular expression pattern to match all IANA top-level domains.
* @deprecated This API is deprecated. See {@link #TOP_LEVEL_DOMAIN_STR}.
*/
@Deprecated
public static final Pattern TOP_LEVEL_DOMAIN =
Pattern.compile(TOP_LEVEL_DOMAIN_STR);
/**
* Regular expression to match all IANA top-level domains for WEB_URL.
* List accurate as of 2011/07/18. List taken from:
* http://data.iana.org/TLD/tlds-alpha-by-domain.txt
* This pattern is auto-generated by frameworks/ex/common/tools/make-iana-tld-pattern.py
*
* @deprecated This API is deprecated. See {@link #TOP_LEVEL_DOMAIN_STR}.
*/
@Deprecated
public static final String TOP_LEVEL_DOMAIN_STR_FOR_WEB_URL =
"(?:"
+ "(?:aero|arpa|asia|a[cdefgilmnoqrstuwxz])"
+ "|(?:biz|b[abdefghijmnorstvwyz])"
+ "|(?:cat|com|coop|c[acdfghiklmnoruvxyz])"
+ "|d[ejkmoz]"
+ "|(?:edu|e[cegrstu])"
+ "|f[ijkmor]"
+ "|(?:gov|g[abdefghilmnpqrstuwy])"
+ "|h[kmnrtu]"
+ "|(?:info|int|i[delmnoqrst])"
+ "|(?:jobs|j[emop])"
+ "|k[eghimnprwyz]"
+ "|l[abcikrstuvy]"
+ "|(?:mil|mobi|museum|m[acdeghklmnopqrstuvwxyz])"
+ "|(?:name|net|n[acefgilopruz])"
+ "|(?:org|om)"
+ "|(?:pro|p[aefghklmnrstwy])"
+ "|qa"
+ "|r[eosuw]"
+ "|s[abcdeghijklmnortuvyz]"
+ "|(?:tel|travel|t[cdfghjklmnoprtvwz])"
+ "|u[agksyz]"
+ "|v[aceginu]"
+ "|w[fs]"
+ "|(?:\u03b4\u03bf\u03ba\u03b9\u03bc\u03ae|\u0438\u0441\u043f\u044b\u0442\u0430\u043d\u0438\u0435|\u0440\u0444|\u0441\u0440\u0431|\u05d8\u05e2\u05e1\u05d8|\u0622\u0632\u0645\u0627\u06cc\u0634\u06cc|\u0625\u062e\u062a\u0628\u0627\u0631|\u0627\u0644\u0627\u0631\u062f\u0646|\u0627\u0644\u062c\u0632\u0627\u0626\u0631|\u0627\u0644\u0633\u0639\u0648\u062f\u064a\u0629|\u0627\u0644\u0645\u063a\u0631\u0628|\u0627\u0645\u0627\u0631\u0627\u062a|\u0628\u06be\u0627\u0631\u062a|\u062a\u0648\u0646\u0633|\u0633\u0648\u0631\u064a\u0629|\u0641\u0644\u0633\u0637\u064a\u0646|\u0642\u0637\u0631|\u0645\u0635\u0631|\u092a\u0930\u0940\u0915\u094d\u0937\u093e|\u092d\u093e\u0930\u0924|\u09ad\u09be\u09b0\u09a4|\u0a2d\u0a3e\u0a30\u0a24|\u0aad\u0abe\u0ab0\u0aa4|\u0b87\u0ba8\u0bcd\u0ba4\u0bbf\u0baf\u0bbe|\u0b87\u0bb2\u0b99\u0bcd\u0b95\u0bc8|\u0b9a\u0bbf\u0b99\u0bcd\u0b95\u0baa\u0bcd\u0baa\u0bc2\u0bb0\u0bcd|\u0baa\u0bb0\u0bbf\u0b9f\u0bcd\u0b9a\u0bc8|\u0c2d\u0c3e\u0c30\u0c24\u0c4d|\u0dbd\u0d82\u0d9a\u0dcf|\u0e44\u0e17\u0e22|\u30c6\u30b9\u30c8|\u4e2d\u56fd|\u4e2d\u570b|\u53f0\u6e7e|\u53f0\u7063|\u65b0\u52a0\u5761|\u6d4b\u8bd5|\u6e2c\u8a66|\u9999\u6e2f|\ud14c\uc2a4\ud2b8|\ud55c\uad6d|xn\\-\\-0zwm56d|xn\\-\\-11b5bs3a9aj6g|xn\\-\\-3e0b707e|xn\\-\\-45brj9c|xn\\-\\-80akhbyknj4f|xn\\-\\-90a3ac|xn\\-\\-9t4b11yi5a|xn\\-\\-clchc0ea0b2g2a9gcd|xn\\-\\-deba0ad|xn\\-\\-fiqs8s|xn\\-\\-fiqz9s|xn\\-\\-fpcrj9c3d|xn\\-\\-fzc2c9e2c|xn\\-\\-g6w251d|xn\\-\\-gecrj9c|xn\\-\\-h2brj9c|xn\\-\\-hgbk6aj7f53bba|xn\\-\\-hlcj6aya9esc7a|xn\\-\\-j6w193g|xn\\-\\-jxalpdlp|xn\\-\\-kgbechtv|xn\\-\\-kprw13d|xn\\-\\-kpry57d|xn\\-\\-lgbbat1ad8j|xn\\-\\-mgbaam7a8h|xn\\-\\-mgbayh7gpa|xn\\-\\-mgbbh1a71e|xn\\-\\-mgbc0a9azcg|xn\\-\\-mgberp4a5d4ar|xn\\-\\-o3cw4h|xn\\-\\-ogbpf8fl|xn\\-\\-p1ai|xn\\-\\-pgbs0dh|xn\\-\\-s9brj9c|xn\\-\\-wgbh1c|xn\\-\\-wgbl6a|xn\\-\\-xkc2al3hye2a|xn\\-\\-xkc2dl3a5ee0h|xn\\-\\-yfro4i67o|xn\\-\\-ygbi2ammx|xn\\-\\-zckzah|xxx)"
+ "|y[et]"
+ "|z[amw]))";
/**
* Good characters for Internationalized Resource Identifiers (IRI).
* This comprises most common used Unicode characters allowed in IRI
* as detailed in RFC 3987.
* Specifically, those two byte Unicode characters are not included.
*/
public static final String GOOD_IRI_CHAR =
"a-zA-Z0-9\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF";
public static final Pattern IP_ADDRESS
= Pattern.compile(
"((25[0-5]|2[0-4][0-9]|[0-1][0-9]{2}|[1-9][0-9]|[1-9])\\.(25[0-5]|2[0-4]"
+ "[0-9]|[0-1][0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(25[0-5]|2[0-4][0-9]|[0-1]"
+ "[0-9]{2}|[1-9][0-9]|[1-9]|0)\\.(25[0-5]|2[0-4][0-9]|[0-1][0-9]{2}"
+ "|[1-9][0-9]|[0-9]))");
/**
* RFC 1035 Section 2.3.4 limits the labels to a maximum 63 octets.
*/
private static final String IRI
= "[" + GOOD_IRI_CHAR + "]([" + GOOD_IRI_CHAR + "\\-]{0,61}[" + GOOD_IRI_CHAR + "]){0,1}";
private static final String GOOD_GTLD_CHAR =
"a-zA-Z\u00A0-\uD7FF\uF900-\uFDCF\uFDF0-\uFFEF";
private static final String GTLD = "[" + GOOD_GTLD_CHAR + "]{2,63}";
private static final String HOST_NAME = "(" + IRI + "\\.)+" + GTLD;
public static final Pattern DOMAIN_NAME
= Pattern.compile("(" + HOST_NAME + "|" + IP_ADDRESS + ")");
/**
* Regular expression pattern to match most part of RFC 3987
* Internationalized URLs, aka IRIs. Commonly used Unicode characters are
* added.
*/
public static final Pattern WEB_URL = Pattern.compile(
"((?:(http|https|Http|Https|rtsp|Rtsp):\\/\\/(?:(?:[a-zA-Z0-9\\$\\-\\_\\.\\+\\!\\*\\'\\(\\)"
+ "\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,64}(?:\\:(?:[a-zA-Z0-9\\$\\-\\_"
+ "\\.\\+\\!\\*\\'\\(\\)\\,\\;\\?\\&\\=]|(?:\\%[a-fA-F0-9]{2})){1,25})?\\@)?)?"
+ "(?:" + DOMAIN_NAME + ")"
+ "(?:\\:\\d{1,5})?)" // plus option port number
+ "(\\/(?:(?:[" + GOOD_IRI_CHAR + "\\;\\/\\?\\:\\@\\&\\=\\#\\~" // plus option query params
+ "\\-\\.\\+\\!\\*\\'\\(\\)\\,\\_])|(?:\\%[a-fA-F0-9]{2}))*)?"
+ "(?:\\b|$)"); // and finally, a word boundary or end of
// input. This is to stop foo.sure from
// matching as foo.su
public static final Pattern EMAIL_ADDRESS
= Pattern.compile(
"[a-zA-Z0-9\\+\\.\\_\\%\\-\\+]{1,256}" +
"\\@" +
"[a-zA-Z0-9][a-zA-Z0-9\\-]{0,64}" +
"(" +
"\\." +
"[a-zA-Z0-9][a-zA-Z0-9\\-]{0,25}" +
")+"
);
/**
* This pattern is intended for searching for things that look like they
* might be phone numbers in arbitrary text, not for validating whether
* something is in fact a phone number. It will miss many things that
* are legitimate phone numbers.
*
* <p> The pattern matches the following:
* <ul>
* <li>Optionally, a + sign followed immediately by one or more digits. Spaces, dots, or dashes
* may follow.
* <li>Optionally, sets of digits in parentheses, separated by spaces, dots, or dashes.
* <li>A string starting and ending with a digit, containing digits, spaces, dots, and/or dashes.
* </ul>
*/
public static final Pattern PHONE
= Pattern.compile( // sdd = space, dot, or dash
"(\\+[0-9]+[\\- \\.]*)?" // +<digits><sdd>*
+ "(\\([0-9]+\\)[\\- \\.]*)?" // (<digits>)<sdd>*
+ "([0-9][0-9\\- \\.]+[0-9])"); // <digit><digit|sdd>+<digit>
/**
* Convenience method to take all of the non-null matching groups in a
* regex Matcher and return them as a concatenated string.
*
* @param matcher The Matcher object from which grouped text will
* be extracted
*
* @return A String comprising all of the non-null matched
* groups concatenated together
*/
public static final String concatGroups(Matcher matcher) {
StringBuilder b = new StringBuilder();
final int numGroups = matcher.groupCount();
for (int i = 1; i <= numGroups; i++) {
String s = matcher.group(i);
if (s != null) {
b.append(s);
}
}
return b.toString();
}
/**
* Convenience method to return only the digits and plus signs
* in the matching string.
*
* @param matcher The Matcher object from which digits and plus will
* be extracted
*
* @return A String comprising all of the digits and plus in
* the match
*/
public static final String digitsAndPlusOnly(Matcher matcher) {
StringBuilder buffer = new StringBuilder();
String matchingRegion = matcher.group();
for (int i = 0, size = matchingRegion.length(); i < size; i++) {
char character = matchingRegion.charAt(i);
if (character == '+' || Character.isDigit(character)) {
buffer.append(character);
}
}
return buffer.toString();
}
/**
* Do not create this static utility class.
*/
private Patterns() {}
}
Answer 3:
我会尝试一个标准的“你为什么做这样说？” 回答......你知道java.net.URL ？
URL url = new URL(stringURL);
上面的代码将抛出MalformedURLException ，如果它不能解析URL。
Answer 4:
与所有建议的方法的问题：所有的正则表达式是验证
所有的正则表达式为基础的代码是过度设计：它会找到唯一有效的URL！ 作为一个样本，它会忽略任何东西开始以“http：//”和其内部具有非ASCII字符。
更：我也遇到过1-2秒的非常小的，简单的句子，没有什么具体的处理时间（单线程的，专用的）与Java正则表达式包（过滤电子邮件从文本地址）; Java 6中的正则表达式可能错误...
最简单的/最快的解决办法是使用的StringTokenizer将文本分成标记，删除开始标记的“http：//”等，并再次置标记为文本。
如果你想过滤来自文本电子邮件（因为以后你会做NLP人员等） - 只是删除包含所有标记“@”内。
这是简单的文字，其中的Java 6的正则表达式失败。 尝试在爪哇divverent变种。 这需要每个正则表达式的通话约1000毫秒，在长时间运行单线程测试应用程序：
pattern = Pattern.compile("[A-Za-z0-9](([_\\.\\-]?[a-zA-Z0-9]+)*)@([A-Za-z0-9]+)(([\\.\\-]?[a-zA-Z0-9]+)*)\\.([A-Za-z]{2,})", Pattern.CASE_INSENSITIVE);
"Avalanna is such a sweet little girl! It would b heartbreaking if cancer won. She's so precious! #BeliebersPrayForAvalanna");
"@AndySamuels31 Hahahahahahahahahhaha lol, you don't look like a girl hahahahhaahaha, you are... sexy.";
不要依赖于正则表达式，如果你只需要过滤的话“@”，“HTTP：//”，“FTP：//”，“电子邮件地址”; 这是巨大的工程开销。
如果你真的想用正则表达式与Java，尝试自动机
Answer 5:
在与billjamesdev答案线，这里是另一种方法来验证URL，而无需使用正则表达式：
从Apache的共享验证的lib，看类UrlValidator 。 一些示例代码：
构建以“http”的有效方案一UrlValidator和“https”开头。
String[] schemes = {"http","https"}.
UrlValidator urlValidator = new UrlValidator(schemes);
if (urlValidator.isValid("ftp://foo.bar.com/")) {
System.out.println("url is valid");
} else {
System.out.println("url is invalid");
}
prints "url is invalid"
相反，如果使用的是默认的构造函数。
UrlValidator urlValidator = new UrlValidator();
if (urlValidator.isValid("ftp://foo.bar.com/")) {
System.out.println("url is valid");
} else {
System.out.println("url is invalid");
}
打印出“网址有效”
Answer 6:
这工作太：
String regex = "\\b(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]";
注意：
String regex = "<\\b(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]>"; // matches <http://google.com>
String regex = "<^(https?|ftp|file)://[-a-zA-Z0-9+&@#/%?=~_|!:,.;]*[-a-zA-Z0-9+&@#/%=~_|]>"; // does not match <http://google.com>
所以，可能是第一个是用于一般用途更加有用。
Answer 7:
当使用从使用RegexBuddy的图书馆正则表达式，一定要使用相同的匹配模式，在自己的代码从库中的正则表达式。 如果您生成使用标签上的源代码片段，使用RegexBuddy将自动设置源代码片段正确的匹配选项。 如果你复制/粘贴正则表达式，你必须自己做。
在这种情况下，其他人指出的那样，你错过了不区分大小写选项。
文章来源: Regular expression to match URLs in Java
