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 = "^(我说(了)?|(我)?跟你说|(我)?说的是)?请?你?(.{0,2}我)?(把)?(音乐|歌曲|音响|音箱|播放)?(暂停|停)(下|一下|一会|一会儿)?(音乐|播放|音响|音箱|歌曲|音乐播放器)?(了)?(听到(了)?(吗|没|没有)|(你)?还放)?.{0,1}$"; final String string = "我不听了\n" + "你别放了\n" + "我不想听了\n" + "别放了\n" + "我要听音乐\n" + "我不要听\n" + "我不听\n" + "别放了啊\n" + "跟你说别放了\n" + "你别放了听到没\n" + "你别放了还放\n" + "别放了你\n" + "你结束\n" + "你别放了啊\n" + "快把音乐关上\n\n\n" + "关闭音响\n" + "关闭音乐\n" + "关掉音乐\n" + "关掉播放器\n" + "你关掉音乐\n" + "你给我关掉音乐\n\n" + "暂停音乐\n" + "把音乐停下来\n" + "你把音乐停下来\n" + "暂停播放\n" + "暂停音乐播放器\n" + "给我停下\n" + "停下来\n" + "音乐停下来\n" + "暂停\n" + "你给我停下\n" + "快给我停下\n" + "停\n" + "暂停一下呗\n" + "停下\n\n" + "唱的真难听\n" + "好难听\n" + "真难听啊\n" + "不好听\n" + "不喜欢\n" + "真的不喜欢\n" + "不喜欢这首歌\n" + "不喜欢这个\n" + "你唱的太难听了\n" + "好难听\n\n" + "不想听音乐\n" + "别放音乐\n" + "不听音乐\n" + "想听周杰伦的歌\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