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
  • 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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?ms)\\<test\\s(?P<tmp>.*?)\\<\\/test\\>"; final String string = "<?xml version=\"1.0\" encoding=\"UTF-8\" ?>\n" + " <unitData endtime=\"2019-09-30T05:39:08+02:00\" equipment=\"eq1\" equipmentClass=\"eqc1\" locale=\"german\" operator=\"ADMINISTRATOR\" senderID=\"sender1\" starttime=\"2019-09-30T05:38:09+02:00\" state=\"nok\" unit=\"74375513159930675\" xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\" xsi:noNamespaceSchemaLocation=\"unitData-1.1.xsd\">\n" + " <subUnitData position=\"1\" positionType=\"Panel Nr.\" state=\"ok\" subUnit=\"74375513159930675\">\n" + " <test description=\"A10-007 7437551\" name=\"CU102_BAY2_QR\" testResultCode=\"passed\">\n" + " <subTest name=\"Verbindung zum Pr³fling aufbauen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Initialisierung\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Fehlerflag lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ID lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Sachnummer lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Trigger setzen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ADC Abschalten\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " </test>\n" + " </subUnitData>\n" + " <subUnitData position=\"2\" positionType=\"Panel Nr.\" state=\"ok\" subUnit=\"74375513159930676\">\n" + " <test description=\"A10-007 7437551\" name=\"CU102_BAY2_QR\" testResultCode=\"passed\">\n" + " <subTest name=\"Verbindung zum Pr³fling aufbauen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Initialisierung\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Fehlerflag lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ID lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Sachnummer lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Trigger setzen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ADC Abschalten\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " </test>\n" + " </subUnitData>\n" + " <subUnitData position=\"3\" positionType=\"Panel Nr.\" state=\"ok\" subUnit=\"74375513159930678\">\n" + " <test description=\"A10-007 7437551\" name=\"CU102_BAY2_QR\" testResultCode=\"passed\">\n" + " <subTest name=\"Verbindung zum Pr³fling aufbauen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Initialisierung\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Fehlerflag lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ID lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Sachnummer lesen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"Trigger setzen\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " <subTest name=\"ADC Abschalten\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " </test>\n" + " </subUnitData>\n" + " <subUnitData position=\"4\" positionType=\"Panel Nr.\" state=\"nok\" subUnit=\"74375513159930677\">\n" + " <test description=\"A10-007 7437551\" name=\"CU102_BAY2_QR\" testResultCode=\"failed\">\n" + " <subTest name=\"FLOAT\" testPosition=\"unknown\">\n" + " <subPositions>\n" + " <subPosition name=\"{27}\"/>\n" + " </subPositions>\n" + " <subTestResult testResultClass=\"fail\" testResultCode=\"failed\"/>\n" + " </subTest>\n" + " <subTest name=\"Components not tested\" testPosition=\"unknown\">\n" + " <subTestResult testResultClass=\"pass\" testResultCode=\"passed\"/>\n" + " </subTest>\n" + " </test>\n" + " </subUnitData>\n" + " </unitData>\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