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

/
/
g

Test String

Substitution

Processing...

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 = "(?:(?!<(?:field|exclGroup)(?!\\w)(?>\"[\\S\\s]*?\"|'[\\S\\s]*?'|(?:(?!\\/>)[^>])?)+>)[\\S\\s])*(?><(field|exclGroup)(?=(?:[^>\"']|\"[^\"]*\"|'[^']*')*?\\sname\\s*=\\s*(?:(['\"])([\\S\\s]*?)\\2))\\s+(?>\"[\\S\\s]*?\"|'[\\S\\s]*?'|(?:(?!\\/>)[^>])?)+>)(?:(?&core)|)<\\/\\1\\s*>(?:(?!<(?:field|exclGroup)(?!\\w)(?>\"[\\S\\s]*?\"|'[\\S\\s]*?'|(?:(?!\\/>)[^>])?)+>)[\\S\\s])*(?(DEFINE)(?<core>(?>(?><([\\w:]+)(?>\"[\\S\\s]*?\"|'[\\S\\s]*?'|(?:(?!\\/>)[^>])?)+>)(?:(?&core)|)<\\/\\5\\s*>|(?!<\\/[\\w:]+\\s*>)(?>[\\S\\s]))+))"; final String string = "<field xmlns=\"http://www.xfa.org/schema/xfa-template/2.8/\" y=\"0in\" x=\"0.343mm\" w=\"8.881pt\" h=\"9.108pt\" name=\"detcon_recreation_only\">\n" + " <ui>\n" + " <checkButton size=\"8.881pt\">\n" + " <border>\n" + " <edge stroke=\"lowered\"/>\n" + " <fill/>\n" + " </border>\n" + " </checkButton>\n" + " </ui>\n" + " <font size=\"0pt\" typeface=\"Adobe Pi Std\"/>\n" + " <para vAlign=\"middle\"/>\n" + " <value>\n" + " <text>0</text>\n" + " </value>\n" + " <items>\n" + " <text>1</text>\n" + " <text>0</text>\n" + " <text/>\n" + " </items>\n" + "</field>\n" + "<field xmlns=\"http://www.xfa.org/schema/xfa-template/2.8/\" name=\"detcon_special_housing\" y=\"5.393mm\" w=\"27.94mm\" h=\"4.134mm\" x=\"0.343mm\">\n" + " <ui>\n" + " <choiceList>\n" + " <border>\n" + " <edge stroke=\"lowered\"/>\n" + " </border>\n" + " <margin/>\n" + " </choiceList>\n" + " </ui>\n" + " <font typeface=\"Arial Narrow\" size=\"6pt\"/>\n" + " <margin topInset=\"0mm\" bottomInset=\"0mm\" leftInset=\"0mm\" rightInset=\"0mm\"/>\n" + " <para vAlign=\"middle\"/>\n" + " <value>\n" + " <text>NA</text>\n" + " </value>\n" + " <items>\n" + " <text>Not Applicable</text>\n" + " <text>Hotel Component</text>\n" + " </items>\n" + " <items save=\"1\" presence=\"hidden\">\n" + " <text>NA</text>\n" + " <text>HC</text>\n" + " </items>\n" + "</field>\n" + "<exclGroup xmlns=\"http://www.xfa.org/schema/xfa-template/2.8/\" name=\"detcon_photo_taken\" x=\"0in\" y=\"0in\">\n" + " <?templateDesigner itemValuesSpecified 1?>\n" + " <field w=\"12.446mm\" h=\"3.825mm\" name=\"lb_yes\">\n" + " <ui>\n" + " <checkButton size=\"1.7639mm\" shape=\"round\">\n" + " <border>\n" + " <?templateDesigner StyleID apcb1?>\n" + " <edge/>\n" + " <fill/>\n" + " </border>\n" + " </checkButton>\n" + " </ui>\n" + " <font typeface=\"Myriad Pro\"/>\n" + " <margin leftInset=\"1mm\" rightInset=\"1mm\"/>\n" + " <para vAlign=\"middle\"/>\n" + " <caption placement=\"right\" reserve=\"7.698mm\">\n" + " <para vAlign=\"middle\" spaceAbove=\"0pt\" spaceBelow=\"0pt\" textIndent=\"0pt\" marginLeft=\"0pt\" marginRight=\"0pt\"/>\n" + " <font size=\"8pt\" typeface=\"Arial Narrow\" baselineShift=\"0pt\"/>\n" + " <value>\n" + " <text>YES</text>\n" + " </value>\n" + " </caption>\n" + " <value>\n" + " <text xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:nil=\"true\"/>\n" + " </value>\n" + " <items>\n" + " <text>1</text>\n" + " </items>\n" + " </field>\n" + " <field w=\"28.702mm\" h=\"3.825mm\" name=\"lb_no\" x=\"13.233mm\">\n" + " <ui>\n" + " <checkButton size=\"1.7639mm\" shape=\"round\">\n" + " <border>\n" + " <?templateDesigner StyleID apcb1?>\n" + " <edge/>\n" + " <fill/>\n" + " </border>\n" + " </checkButton>\n" + " </ui>\n" + " <font typeface=\"Myriad Pro\"/>\n" + " <margin leftInset=\"1mm\" rightInset=\"1mm\"/>\n" + " <para vAlign=\"middle\"/>\n" + " <caption placement=\"right\" reserve=\"23.954mm\">\n" + " <para vAlign=\"middle\" spaceAbove=\"0pt\" spaceBelow=\"0pt\" textIndent=\"0pt\" marginLeft=\"0pt\" marginRight=\"0pt\"/>\n" + " <font size=\"8pt\" typeface=\"Arial Narrow\" baselineShift=\"0pt\"/>\n" + " <value>\n" + " <text>NO (see comments)</text>\n" + " </value>\n" + " </caption>\n" + " <value>\n" + " <text xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:nil=\"true\"/>\n" + " </value>\n" + " <items>\n" + " <text>0</text>\n" + " </items>\n" + " </field>\n" + " <border>\n" + " <edge presence=\"hidden\"/>\n" + " </border>\n" + " <?templateDesigner expand 1?></exclGroup>"; final String subst = "VALUES (12345,\"$3\",\"/Tx\", \"\", \"N\", \"Y\"),\\r\\n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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