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

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 = "([\\w*-′]*([\\[(]([\\[(]?[a-zA-Zα-ωΑ-Ωµ\\-′,:]+\\d?[+-]?[\\])]?)+[\\])\\d+-]{1,})[\\w*-′]*)|(([A-z]+[a-z]*\\d)+([A-z]+[a-z]*\\d?)*)"; final String string = "\"Fe(iii) or iron(iii) [Fe(Rtpen)X](A)n, n = 1, 2; X = Cl, Br; Rtpen = N-alkyl-N,N′,N′-tris(2-pyridylmethyl)ethane-1,2-diamine, alkyl = R = CH3CH2, CH3CH2CH2, HOCH2CH2, (CH3)2CH, C6H5, and C6H5CH2; A = ClO4, PF6.\"\n" + "\"iron(iii) \n" + "[Fe(Rtpen)(η1-OCH3)]2+ \n" + "[Fe(Rtpen)(η1-OOH)]2+ from iron(ii)\"\n" + "\"[FeIIIOOH]2+ rather than [FeIIIOO]+ species are the p\"\n" + "[(Rtpen)Fe(µ,η2:η2-O2)Fe(Rtpen)]4+\n" + "iron(iii)\n" + "Fe(iii)\n" + "[FeIIIOOH]2+\n" + "[Fe(Rtpen)Cl]+\n" + "[Fe(Rtpen)(η1-OOH)]2+\n" + "[Fe(Rtpen)X](A)n\n" + "[(Rtpen)Fe(µ,η2:η2-O2)Fe(Rtpen)]4+\n" + " Fe(Rtpen)(η2-OO)]+,\n" + "N′-tris(2-pyridylmethyl)ethane-1,2-diamine\n" + "of [Fe(Rtpen)(η1-OOH)]2+ pro\n" + " (ESR, UV-vis, ESI MS) \n" + " [Fe(Rtpen)(η1-OOH)]2+, R = CH3CH2, CH3CH2CH2, HOCH2CH2, (CH3)2CH, C6H5, and C6H5CH2.\n" + "f [Fe(ettpen)Cl]ClO4 instead of [Fe(bztpen)Cl]ClO4 \n" + "[Fe(Rtpen)Cl]A, A = ClO4, PF6, are as expected ESR silent.\n" + "[Fe(Rtpen)Cl](PF6) and [Fe(Rtpen)Cl](PF6)2\n" + "e µ-oxo complex [(bztpen)ClFe(µ-O)FeCl(bztpen)](PF6)2 which could be isolated.\n" + "H2O\n" + "[Fe(bztpen)Cl](ClO4)2\n" + " solution at 100 K, a rhombic low-spin signal (g = 2.32, 2.14, 1.93) is present in the spectra of the Fe(iii) complexes (Fig. 3a)\n" + ").\n\n" + "metpen–Fe(iii)–peroxide complexes, lead to assignment of end-on coordination for the hydroperoxide species, e.g., [Fe(Rtpen)(η1-OOH)]2+, and side-on (η2) peroxide coordination in their deprotonated derivatives, e.g., [Fe(Rtpen)(η2-OO)]+ (Scheme 1)"; final Pattern pattern = Pattern.compile(regex); 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