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

r"
"
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 = "(above|below|title|data[0-9]*|header[0-9]*|caption|above|label[0-9]*) *= +([^\\{\\}|\\n]+)[^| \\n]"; final String string = "{{Infobox\n" + " |name = {{subst:PAGENAME}}\n" + " |bodystyle = \n\n" + " |titlestyle = \n" + " |abovestyle = background:#cfc;\n" + " |subheaderstyle =\n" + " |title = Test Infobox\n" + " |above = Above text\n" + " |subheader = Subheader above image\n" + " |subheader2 = Second subheader\n\n" + " |imagestyle = \n" + " |captionstyle = \n" + " | image = [[File:example.png|200px|alt=Example alt text]]\n" + " |caption = Caption displayed below example.png\n\n" + " |headerstyle = background:#ccf;\n" + " |labelstyle = background:#ddf;\n" + " |datastyle = \n\n" + " |header1 = Header defined alone\n" + " | label1 = \n" + " | data1 = \n" + " |header2 = \n" + " | label2 = Label defined alone does not display (needs data, or is suppressed)\n" + " | data2 = \n" + " |header3 =\n" + " | label3 = \n" + " | data3 = Data defined alone\n" + " |header4 = All three defined (header, label, data, all with same number)\n" + " | label4 = does not display (same number as a header)\n" + " | data4 = does not display (same number as a header)\n" + " |header5 =\n" + " | label5 = Label and data defined (label)\n" + " | data5 = Label and data defined (data)\n\n" + " |belowstyle = background:#ddf;\n" + " |below = Below text\n" + "}}\n\n" + "{{Infobox\n" + " | title = Top level title\n" + " | header1 = {{Infobox | decat = yes | child = yes\n" + " | title = First subsection\n" + " | label1= Label 1.1\n" + " | data1 = Data 1.1\n" + " }}\n" + " | header2 = {{Infobox | decat = yes | child = yes\n" + " | title = Second subsection\n" + " | label1= Label 2.1\n" + " | data1 = Data 2.1\n" + " }}\n" + " | belowstyle = \n" + " | below = Below text\n" + "}}\n\n" + "{{Infobox\n" + " |name = {{subst:PAGENAME}}\n" + " |bodystyle = width:20em\n\n" + " |titlestyle = \n" + " |title = Test Infobox\n\n" + " |headerstyle = \n" + " |labelstyle = width:33%\n" + " |datastyle = \n\n" + " |header1 = \n" + " | label1 = Label 1\n" + " | data1 = Data 1\n" + " |header2 = \n" + " | label2 = Label 2\n" + " | data2 = Data 2\n" + " |header3 = \n" + " | label3 = Label 3\n" + " | data3 = Data 3\n" + " |header4 = Header 4\n" + " | label4 = \n" + " | data4 = \n" + " |header5 = \n" + " | label5 = Label 5\n" + " | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.\n\n" + " |belowstyle = \n" + " |below = Below text\n" + "}}\n\n\n" + "{{Infobox\n" + " |name = {{subst:PAGENAME}}\n" + " |bodystyle = width:20em\n\n" + " |titlestyle = \n" + " |title = Test Infobox\n\n" + " |headerstyle = \n" + " |labelstyle = width:33%\n" + " |datastyle = \n\n" + " |header1 = \n" + " | label1 = Label 1\n" + " | data1 = Data 1\n" + " |header2 = \n" + " | label2 = Label 2\n" + " | data2 = Data 2\n" + " |header3 = \n" + " | label3 = Label 3\n" + " | data3 = Data 3\n" + " |header4 = Header 4\n" + " | label4 = \n" + " | data4 = \n" + " |header5 = \n" + " | label5 = Label 5\n" + " | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.\n\n" + " |belowstyle = \n" + " |below = Below text\n" + "}}\n\n\n" + "{{Infobox\n" + " |name = {{subst:PAGENAME}}\n" + " |bodystyle = width:20em\n\n" + " |titlestyle = \n" + " |title = Test Infobox\n\n" + " |headerstyle = \n" + " |labelstyle = width:33%\n" + " |datastyle = \n\n" + " |header1 = \n" + " | label1 = Label 1\n" + " | data1 = Data 1\n" + " |header2 = \n" + " | label2 = Label 2\n" + " | data2 = Data 2\n" + " |header3 = \n" + " | label3 = Label 3\n" + " | data3 = Data 3\n" + " |header4 = Header 4\n" + " | label4 = \n" + " | data4 = \n" + " |header5 = \n" + " | label5 = Label 5\n" + " | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.\n\n" + " |belowstyle = \n" + " |below = Below text\n" + "}}\n\n\n" + "{{Infobox\n" + " |name = {{subst:PAGENAME}}\n" + " |bodystyle = width:20em\n\n" + " |titlestyle = \n" + " |title = Test Infobox\n\n" + " |headerstyle = \n" + " |labelstyle = width:33%\n" + " |datastyle = \n\n" + " |header1 = \n" + " | label1 = Label 1\n" + " | data1 = Data 1\n" + " |header2 = \n" + " | label2 = Label 2\n" + " | data2 = Data 2\n" + " |header3 = \n" + " | label3 = Label 3\n" + " | data3 = Data 3\n" + " |header4 = Header 4\n" + " | label4 = \n" + " | data4 = \n" + " |header5 = \n" + " | label5 = Label 5\n" + " | data5 = Data 5: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.\n\n" + " |belowstyle = \n" + " |below = Below text\n" + "}}\n\n\n" + "{{Infobox\n" + " | headerstyle = background-color:#eee;\n" + " | labelstyle = background-color:#eee;\n" + " | header1 = Main 1\n" + " | header2 = Main 2\n" + " | data3 = {{Infobox | subbox = yes\n" + " | headerstyle = background-color:#ccc;\n" + " | labelstyle = background-color:#ddd;\n" + " | header1 = Sub 3-1\n" + " | header2 = Sub 3-2\n" + " | label3 = Label 3-3 | data3 = Data 3-3\n" + " }}\n" + " | data4 = {{Infobox | subbox = yes\n" + " | labelstyle = background-color:#ccc;\n" + " | label1 = Label 4-1 | data1 = Data 4-1\n" + " }}\n" + " | label5 = Label 5 | data5 = Data 5\n" + " | header6 = Main 6\n" + "}}\n\n\n" + "{{Infobox\n" + " | headerstyle = background-color:#eee;\n" + " | labelstyle = background-color:#eee;\n" + " | header1 = Main 1\n" + " | header2 = Main 2\n" + " | data3 = {{Infobox | subbox = yes\n" + " | headerstyle = background-color:#ccc;\n" + " | labelstyle = background-color:#ddd;\n" + " | header1 = Sub 3-1\n" + " | header2 = Sub 3-2\n" + " | label3 = Label 3-3 | data3 = Data 3-3\n" + " }}\n" + " | data4 = {{Infobox | subbox = yes\n" + " | labelstyle = background-color:#ccc;\n" + " | label1 = Label 4-1 | data1 = Data 4-1\n" + " }}\n" + " | label5 = Label 5 | data5 = Data 5\n" + " | header6 = Main 6\n" + "}}\n\n\n\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