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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

"
"
g

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(\\\".*\\\")|\\d+"; final String string = "{\n" + " \"code\": 0,\n" + " \"data\": {\n" + " \"album\": {\n" + " \"count\": 2,\n" + " \"itemlist\": [\n" + " {\n" + " \"docid\": \"24100646\",\n" + " \"id\": \"24100646\",\n" + " \"mid\": \"002mPgSG01LLtu\",\n" + " \"name\": \"无名的人\",\n" + " \"pic\": \"http://y.gtimg.cn/music/photo_new/T002R180x180M000002mPgSG01LLtu_1.jpg\",\n" + " \"singer\": \"毛不易\"\n" + " },\n" + " {\n" + " \"docid\": \"3834888\",\n" + " \"id\": \"3834888\",\n" + " \"mid\": \"0026ttFc17IeE3\",\n" + " \"name\": \"无问\",\n" + " \"pic\": \"http://y.gtimg.cn/music/photo_new/T002R180x180M0000026ttFc17IeE3_1.jpg\",\n" + " \"singer\": \"毛不易\"\n" + " }\n" + " ],\n" + " \"name\": \"专辑\",\n" + " \"order\": 2,\n" + " \"type\": 3\n" + " },\n" + " \"mv\": {\n" + " \"count\": 2,\n" + " \"itemlist\": [\n" + " {\n" + " \"docid\": \"1449642\",\n" + " \"id\": \"1449642\",\n" + " \"mid\": \"001UwAbv4H9QVZ\",\n" + " \"name\": \"牧马城市\",\n" + " \"singer\": \"毛不易\",\n" + " \"vid\": \"k002671le5d\"\n" + " },\n" + " {\n" + " \"docid\": \"1352908\",\n" + " \"id\": \"1352908\",\n" + " \"mid\": \"003bjsSu20ltwY\",\n" + " \"name\": \"像我这样的人\",\n" + " \"singer\": \"毛不易\",\n" + " \"vid\": \"y0026hr4b5e\"\n" + " }\n" + " ],\n" + " \"name\": \"MV\",\n" + " \"order\": 3,\n" + " \"type\": 4\n" + " },\n" + " \"singer\": {\n" + " \"count\": 2,\n" + " \"itemlist\": [\n" + " {\n" + " \"docid\": \"1507534\",\n" + " \"id\": \"1507534\",\n" + " \"mid\": \"001BHDR33FZVZ0\",\n" + " \"name\": \"毛不易\",\n" + " \"pic\": \"http://y.gtimg.cn/music/photo_new/T001R150x150M000001BHDR33FZVZ0_3.jpg\",\n" + " \"singer\": \"毛不易\"\n" + " },\n" + " {\n" + " \"docid\": \"4417724\",\n" + " \"id\": \"4417724\",\n" + " \"mid\": \"000pEm1i1BkmuD\",\n" + " \"name\": \"毛不易的留声机\",\n" + " \"pic\": \"http://y.gtimg.cn/music/photo_new/T001R150x150M000000pEm1i1BkmuD_1.jpg\",\n" + " \"singe\": \"毛不易的留声机\"\n" + " }\n" + " ],\n" + " \"name\": \"歌手\",\n" + " \"order\": 1,\n" + " \"type\": 2\n" + " },\n" + " \"song\": {\n" + " \"count\": 4,\n" + " \"itemlist\": [\n" + " {\n" + " \"docid\": \"203514624\",\n" + " \"id\": \"203514624\",\n" + " \"mid\": \"00375L600p9sxv\",\n" + " \"name\": \"像我这样的人\",\n" + " \"singer\": \"毛不易\"\n" + " }\n" + " {\n" + " \"docid\": \"203451421\",\n" + " \"id\": \"203451421\",\n" + " \"mid\": \"003kLvu04bLGzi\",\n" + " \"name\": \"消愁\",\n" + " \"singer\": \"毛不易\"\n" + " }\n" + " {\n" + " \"docid\": \"213224236\",\n" + " \"id\": \"213224236\",\n" + " \"mid\": \"000uhMwj387EBp\",\n" + " \"name\": \"牧马城市\",\n" + " \"singer\": \"毛不易\"\n" + " }\n" + " {\n" + " \"docid\": \"336582682\",\n" + " \"id\": \"336582682\",\n" + " \"mid\": \"002QhULf16tWw1\",\n" + " \"name\": \"无名的人\",\n" + " \"singer\": \"毛不易\"\n" + " }\n" + " ],\n" + " \"name\": \"单曲\",\n" + " \"order\": 0,\n" + " \"type\": 1\n" + " }\n" + " },\n" + " \"subcode\": 0\n" + "}"; final Pattern pattern = Pattern.compile(regex); 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