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 = "^.{0,1}(陪我一起)?听?你?(再|快|先)?能?(给我)?唱?(啊|一?个|吧|出来|一?首)?歌?(给我听|来听听)?(吧|啊|哇|呗|呀)?((好(么|嘛|吗))|好不好|小万|亲爱的|这么难)?.{0,1}$"; final String string = "你先唱给我听好吗\n" + "快唱啊\n" + "快唱啊你\n\n" + "你唱吧\n" + "你唱一个\n" + "唱一首吧亲爱的\n" + "再唱一首\n" + "你快唱吧\n" + "你能唱出来吗\n" + "唱出来\n" + "唱一个给我听呗好不好\n" + "快唱\n" + "唱\n" + "唱吧\n" + "你唱啊\n" + "唱一个嘛\n" + "唱一个啊\n" + "来听你唱歌\n" + "再给我唱一首呗\n" + "唱歌小万\n" + "你唱首歌给我听呗\n" + "陪我一起唱歌好吗\n" + "听你唱歌这么难\n" + "唱首歌来听听\n\n\n" + "你唱歌好好听啊再给我唱一首呗\n\n" + "我现在就很不开心你唱首歌给我听呗\n\n" + "会不会唱歌，唱首歌来听听"; 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