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

/
/
gmU

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 = "function(.|\\n)*\\{(.|\\n)*if(.|\\n)*function "; final String string = " onRenderComplete: function () {\n" + " pageData.orderingAll = viewModel.tabAllGrid.getOrdering();\n\n" + " if (app.session.features.openNotesAndMessagesFromList_VEA14870) {\n" + " $('#tabAllGrid .connectedMessageIcon').on('click', function (e) {\n\n" + " var $messages = $(e.target),\n" + " $row = $messages.parents('.gridRow'),\n" + " rowId = $row.data('row'),\n" + " rowData = $('#tabAllGrid').vismaGrid('getRowData', rowId);\n" + " postItMessageModal(rowData);\n" + " });\n\n" + " function postItMessageModal(data) {\n" + " var documentType = null;\n" + " var documentId = null;\n" + " var urls = data.invoiceUrl.split('/');\n" + " if (urls.length > 3 && urls[3]) {\n" + " documentType = urls[2];\n" + " var guidRegex = /^[{]?[0-9a-fA-F]{8}[-]?([0-9a-fA-F]{4}[-]?){3}[0-9a-fA-F]{12}[}]?$/;\n" + " if (urls[3].match(guidRegex)) {\n" + " documentId = urls[3];\n" + " } else {\n" + " documentId = urls[4];\n" + " }\n" + " }\n" + " app.shell.viewModel.commentViewModel.getMessagesForGivenDocument(documentType, documentId, false, true);\n" + " };\n" + " }\n" + " },\n" + " initialSelected: initialSelectedAll\n" + " };"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.UNICODE_CHARACTER_CLASS); 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