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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "^我?(想|要)?(到|去)?#都?有?((哪(儿|里)?|(啥|什么|哪些|啥子))((好|可)玩儿?的?(地(方|儿)?)?|好?地(方|儿))去?|(怎么|咋)玩儿?|(什么|啥|哪些)好?((旅游|游玩)?(景点|攻略)|风景区|旅游区))(吗|呢|不|吧|嘛|么|呀|没|啊|阿)?$"; final String string = "\n" + "#怎么玩\n" + "#有哪里好玩的\n" + "#有哪里好玩\n" + "#什么好玩的\n" + "#哪儿好玩\n" + "#什么好玩的地方\n" + "#有什么好玩的\n" + "#有哪好玩的\n" + "#都有什么好玩的\n" + "#有什么好地方\n" + "#啥好玩的\n" + "#有什么可玩的\n" + "#有什么好玩的地\n" + "#有啥可玩的\n" + "#有哪好玩\n" + "#什么景点\n" + "#有什么好玩的呀\n" + "#有什么好玩\n" + "#有哪些好玩的\n" + "#有哪里好玩的地方\n" + "#有啥好玩的没\n" + "#都有哪些好玩的\n" + "#有什么风景区\n" + "#有什么好景点\n" + "#有什么好玩的阿\n" + "#有哪里好玩呀\n" + "#有什么好玩的地儿\n" + "#有什么地方去\n" + "#有什么好玩的没\n" + "#有啥好玩的不\n" + "#哪儿好玩儿\n" + "#有什么可玩儿的\n" + "#哪儿好玩呀\n" + "#有啥好玩的地方\n" + "#什么好玩的呀\n" + "#有什么好玩的地方\n" + "#有啥子好玩的\n" + "#什么好玩儿的\n" + "#都有什么景点\n" + "去#有什么好玩的地方\n" + "我想去#有什么好玩儿的\n" + "去#有什么好玩的呀\n" + "去#有什么好玩\n\n\n" + "去#旅游怎么样\n" + "去#玩什么\n" + "去#玩\n" + "去#玩怎么样\n" + "#去哪里好玩\n" + "#有什么玩的\n" + "#有好玩的么\n" + "#什么地方好玩\n" + "#攻略有吗\n" + "#好玩的地方有哪些\n\n" + "去#的攻略\n" + "#风景区\n" + "去#旅游\n" + "#周边游\n" + "#游玩攻略\n\n\n" + "#有什么可玩的\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