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

/
/
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 = "BN((6(0[0-9]|1[0134]|2[1-9]|3[0-1]))|7(0[68]|1(0|1[A-C])|2([1-4]|5|[7-9])|3[01]))"; final String string = "BN601\n" + "BN602\n" + "BN603\n" + "BN604\n" + "BN605\n" + "BN606\n" + "BN607\n" + "BN608\n" + "BN609\n" + "BN610\n" + "BN611\n" + "BN612\n" + "BN613\n" + "BN614\n" + "BN615\n" + "BN616\n" + "BN617\n" + "BN618\n" + "BN619\n" + "BN620\n" + "BN621\n" + "BN622\n" + "BN623\n" + "BN624\n" + "BN625\n" + "BN626\n" + "BN627\n" + "BN628\n" + "BN629\n" + "BN630\n" + "BN631\n" + "BN632\n" + "BN701\n" + "BN702\n" + "BN703\n" + "BN704\n" + "BN705\n" + "BN706\n" + "BN707\n" + "BN708\n" + "BN709\n" + "BN710\n" + "BN711\n" + "BN711A\n" + "BN711B\n" + "BN711C\n" + "BN711a\n" + "BN711b\n" + "BN711c\n" + "BN712\n" + "BN713\n" + "BN714\n" + "BN715\n" + "BN716\n" + "BN717\n" + "BN718\n" + "BN719\n" + "BN720\n" + "BN721\n" + "BN722\n" + "BN723\n" + "BN724\n" + "BN725\n" + "BN726\n" + "BN727\n" + "BN728\n" + "BN729\n" + "BN730\n" + "BN731\n" + "BN732\n"; 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