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

/
/
msi

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 = "(?smi)^.*tag=\"[A-Z]_([A-Z]{2})_(\\d{4}).*$"; final String string = "<?xml version=\"1.0\"?>\n" + "-<PEGraphic gridSpaceY=\"100\" gridSpaceX=\"100\" bkgdImage=\"\" gridColor=\"#333333\" paperColor=\"#000000\" width=\"19600\" height=\"14200\" version=\"5\">\n" + "<Font height=\"120\" name=\"Arial\"/>\n" + "-<Polyline backFill=\"yes\" backColor=\"#FFFFFF\">\n" + "<Location right=\"6020\" bottom=\"12445\" left=\"6018\" top=\"11741\"/>\n" + "<Pen width=\"2\" style=\"solid\" color=\"#00FF00\"/>\n" + "<Brush style=\"hollow\" color=\"#00FF00\"/>\n" + "<Point y=\"11741\" x=\"6019\"/>\n" + "<Point y=\"12445\" x=\"6019\"/>\n" + "</Polyline>\n" + "-<Polyline backFill=\"yes\" backColor=\"#E0E0E0\">\n" + "<Location right=\"3365\" bottom=\"12835\" left=\"3363\" top=\"11741\"/>\n" + "<Pen width=\"2\" style=\"solid\" color=\"#00FF00\"/>\n" + "<Brush style=\"hollow\" color=\"#00FF00\"/>\n" + "<Point y=\"11741\" x=\"3364\"/>\n" + "<Point y=\"12835\" x=\"3364\"/>\n" + "</Polyline>\n" + "-<Polyline backFill=\"yes\" backColor=\"#FFFFFF\">\n" + "<Location right=\"4627\" bottom=\"6800\" left=\"4521\" top=\"5100\"/>\n" + "<Pen width=\"2\" style=\"solid\" color=\"#00FF00\"/>\n" + "<Brush style=\"hollow\" color=\"#00FF00\"/>\n" + "<Datasource stepped=\"no\" server=\"USFRPVMESPOLYOL\" map=\"IP_DIMAP\" field=\"VAL\" tag=\"p_dc_1730\"/>\n" + "-<Animation on=\"yes\">\n" + "<AnimationRange color=\"#666666\" image=\"\" text=\"act sp\" max=\"0\" min=\"0\" index=\"1\"/>\n" + "<AnimationRange color=\"#00FF00\" image=\"\" text=\"act sp\" max=\"1\" min=\"1\" index=\"2\"/>\n" + "</Animation>\n" + "<Point y=\"5100\" x=\"4627\"/>\n" + "<Point y=\"6800\" x=\"4627\"/>\n" + "</Polyline>\n" + "-<Polyline backFill=\"yes\" backColor=\"#FFFFFF\">\n" + "<Location right=\"3719\" bottom=\"4394\" left=\"1918\" top=\"3300\"/>\n" + "<Pen width=\"2\" style=\"solid\" color=\"#00FF00\"/>\n" + "<Brush style=\"hollow\" color=\"#00FF00\"/>\n" + "<Datasource stepped=\"no\" server=\"USFRPVMESPOLYOL\" map=\"\" field=\"VAL\" tag=\"P_DC_2103\"/>\n" + "-<Animation on=\"yes\">\n" + "<AnimationRange color=\"#666666\" image=\"\" text=\"act sp\" max=\"0\" min=\"0\" index=\"1\"/>\n" + "<AnimationRange color=\"#00FF00\" image=\"\" text=\"act sp\" max=\"1\" min=\"1\" index=\"2\"/>\n" + "</Animation>\n" + "<Point y=\"4394\" x=\"3718\"/>\n" + "<Point y=\"4098\" x=\"3718\"/>\n" + "<Point y=\"4098\" x=\"1918\"/>\n" + "<Point y=\"3300\" x=\"1918\"/>\n" + "</Polyline>\n"; final String subst = "CG $1($2)"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL | Pattern.CASE_INSENSITIVE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(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