Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

`
`
gm

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?s:(\"name\" : \"(.*?)\".*?作者[:]*</span>[:]*.*?>(.*?)<.*?出版社.*?> (.*?)<.*?>出版年.*?([\\d]{4}-[\\d]).*?定价:</span> (.*?)<.*?ISBN:</span> (.*?)<.*?v:average\"> ([\\d].[\\d]).*?v:votes\">([\\d]+?)<.*?\"rating_per\">(.*?)<.*?\"rating_per\">(.*?)<.*?\"rating_per\">(.*?)<.*?\"rating_per\">(.*?)<.*?\"rating_per\">(.*?)<))"; final String string = "\n" + "<script type=\"application/ld+json\">\n" + "{\n" + " \"@context\":\"http://schema.org\",\n" + " \"@type\":\"Book\",\n" + " \"workExample\": [],\n" + " \"name\" : \"索拉里斯星\",\n\n" + " <span class=\"pl\"> 作者</span>:\n" + " \n" + " \n" + " <a class=\"\" href=\"/search/%E6%96%AF%E5%9D%A6%E5%B0%BC%E6%96%AF%E7%93%A6%E5%A4%AB%C2%B7%E8%8E%B1%E5%A7%86\">[波] 斯坦尼斯瓦夫·莱姆</a>\n" + " </span><br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">出版社:</span> 译林出版社<br/>\n\n" + " \n" + " \n" + " \n\n" + " \n" + " \n" + " \n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">原作名:</span> Solaris<br/>\n\n" + " \n" + " \n" + " \n" + " <span>\n" + " <span class=\"pl\"> 译者</span>:\n" + " \n" + " \n" + " <a class=\"\" href=\"/search/%E9%9D%96%E6%8C%AF%E5%BF%A0\">靖振忠</a>\n" + " </span><br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">出版年:</span> 2021-8<br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">页数:</span> 254<br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">定价:</span> 49.00元<br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">装帧:</span> 平装<br/>\n\n" + " \n" + " \n" + " \n" + " <span class=\"pl\">丛书:</span>&nbsp;<a href=\"https://book.douban.com/series/54333\">译林幻系列</a><br>\n\n" + " \n" + " \n" + " \n" + " \n" + " \n" + " <span class=\"pl\">ISBN:</span> 9787544782173<br/>\n\n" + " \n" + " \n" + " \n\n\n" + "</div>\n\n" + "</div>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n" + " \n\n\n\n\n\n" + "<div id=\"interest_sectl\" class=\"\">\n" + " <div class=\"rating_wrap clearbox\" rel=\"v:rating\">\n" + " <div class=\"rating_logo\">豆瓣评分</div>\n" + " <div class=\"rating_self clearfix\" typeof=\"v:Rating\">\n" + " <strong class=\"ll rating_num \" property=\"v:average\"> 8.7 </strong>\n" + " <span property=\"v:best\" content=\"10.0\"></span>\n" + " <div class=\"rating_right \">\n" + " <div class=\"ll bigstar45\"></div>\n" + " <div class=\"rating_sum\">\n" + " <span class=\"\">\n" + " <a href=\"comments\" class=\"rating_people\"><span property=\"v:votes\">8085</span>人评价</a>\n" + " </span>\n" + " </div>\n\n\n" + " </div>\n" + " </div>\n" + " \n" + " \n" + " \n" + "<span class=\"stars5 starstop\" title=\"力荐\">\n" + " 5星\n" + "</span>\n\n" + " \n" + "<div class=\"power\" style=\"width:64px\"></div>\n\n" + " <span class=\"rating_per\">46.0%</span>\n" + " <br>\n" + " \n" + " \n" + "<span class=\"stars4 starstop\" title=\"推荐\">\n" + " 4星\n" + "</span>\n\n" + " \n" + "<div class=\"power\" style=\"width:54px\"></div>\n\n" + " <span class=\"rating_per\">39.4%</span>\n" + " <br>\n" + " \n" + " \n" + "<span class=\"stars3 starstop\" title=\"还行\">\n" + " 3星\n" + "</span>\n\n" + " \n" + "<div class=\"power\" style=\"width:17px\"></div>\n\n" + " <span class=\"rating_per\">12.5%</span>\n" + " <br>\n" + " \n" + " \n" + "<span class=\"stars2 starstop\" title=\"较差\">\n" + " 2星\n" + "</span>\n\n" + " \n" + "<div class=\"power\" style=\"width:2px\"></div>\n\n" + " <span class=\"rating_per\">1.8%</span>\n" + " <br>\n" + " \n" + " \n" + "<span class=\"stars1 starstop\" title=\"很差\">\n" + " 1星\n" + "</span>\n\n" + " \n" + "<div class=\"power\" style=\"width:0px\"></div>\n\n" + " <span class=\"rating_per\">0.3%</span>\n\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html