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

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 = "(?mi)((?:password=|user=)[^\\n]*$|\\<property key=\\\"variableNames\\\"\\/\\>\\n|\\<property key=\\\"variableValues\\\"\\/\\>\\n)"; final String string = "<maplayer simplifyAlgorithm=\"0\" minimumScale=\"0\" maximumScale=\"2500\" simplifyDrawingHints=\"0\" readOnly=\"0\" minLabelScale=\"0\" maxLabelScale=\"1e+08\" simplifyDrawingTol=\"1\" geometry=\"Point\" simplifyMaxScale=\"1\" type=\"vector\" hasScaleBasedVisibilityFlag=\"1\" simplifyLocal=\"1\" scaleBasedLabelVisibilityFlag=\"0\">\n" + " <id></id>\n" + " <datasource>port=1521 user=test_user password=test_passwd</datasource>\n" + " <keywordList>\n" + " <value></value>\n" + " </keywordList>\n" + " <featformsuppress>0</featformsuppress>\n" + " <editorlayout>generatedlayout</editorlayout>\n" + " <widgets/>\n" + " <conditionalstyles>\n" + " <rowstyles/>\n" + " <fieldstyles/>\n" + " </conditionalstyles>\n" + " </maplayer>\n" + " </projectlayers>\n" + " <properties>\n" + " <Variables>\n" + " <variableNames type=\"QStringList\">\n" + " <value>paswd</value>\n" + " <value>user</value>\n" + " </variableNames>\n" + " <variableValues type=\"QStringList\">\n" + " <value>5zdgf</value>\n" + " <value>dgdgdgfdg</value>\n" + " </variableValues>\n" + " </Variables>\n" + " <customproperties>\n" + " <property key=\"labeling/textColorR\" value=\"0\"/>\n" + " <property key=\"labeling/textTransp\" value=\"0\"/>\n" + " <property key=\"labeling/upsidedownLabels\" value=\"0\"/>\n" + " <property key=\"labeling/useSubstitutions\" value=\"false\"/>\n" + " <property key=\"labeling/wrapChar\" value=\"\"/>\n" + " <property key=\"labeling/xOffset\" value=\"0\"/>\n" + " <property key=\"labeling/yOffset\" value=\"0\"/>\n" + " <property key=\"labeling/zIndex\" value=\"0\"/>\n" + " <property key=\"variableNames\"/>\n" + " <property key=\"variableValues\"/>\n" + " </customproperties>"; final String subst = ""; 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