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

/
/

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 = "Instrument Method\\s*[=:-]\\s*(?<dm>.*)"; final String string = "This data was acquired in Method&Run Control.\n" + "The MSD parameters were saved in the msdiag register file.\n" + "This msparms.txt file was built using the values from the msdiag register.\n" + "Some parameters normally reported under MSData acquisition in Tune \n" + "may be missing from this msparms.txt file. You may be able to read these \n" + "values from Data Analysis. These items are marked with an asterisk (*).\n" + " \n" + " \n" + " \n" + "File : C:\\HPCHEM\\1\\DATA\\FIA.D\n" + "Operator : Apps Chemist\n" + "Date acquired : Wed Apr 09 17:50:26 1997\n" + "Instrument Method : Appsprite2\n" + " \n" + " \n" + "Sample information\n" + "----------------------------------\n" + "Sample name : 50 ng caffeine\n" + "Misc info : 50 ng Caffeine run in condensed mode varying fragmentor\n" + " \n" + " \n" + "MS parameters\n" + "----------------------------------\n" + "Tune File : C:\\HPCHEM\\1\\1946TUNE\\atunes.tun\n" + "Skim1 : Not Applicable\n" + "Skim2 : 8.0 V \n" + "Ion Energy : 5.0 V \n" + "Lens1 : 1.4 V \n" + "Lens2 : 27 V \n" + "Iris : 350 V \n" + "HED : 10000 V \n" + "Width Gain : -70 \n" + "Width Offset : Variable \n" + " Mass : Value \n" + " --------------------------\n" + " 118.10 : -11 \n" + " 622.03 : -14 \n" + " 922.01 : -2 \n" + " 1521.97 : -8 \n" + " 2121.93 : -13 \n" + " 2721.89 : -12 \n" + " --------------------------\n" + "Mass Gain : 4.40 \n" + "Mass Offset : Variable \n" + " Mass : Value \n" + " --------------------------\n" + " 118.10 : 0 \n" + " 622.03 : 0 \n" + " 922.01 : 0 \n" + " 1521.97 : 0 \n" + " 2121.93 : 0 \n" + " 2721.89 : 0 \n" + " --------------------------\n" + "Quad DC : 0.00 V \n" + "Octopole Peak : 300 V \n" + "Octopole Knee : 307 Da \n" + "Mass Filter : Gaussian \n" + "Mass Filter Width : 0.30 Da \n"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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