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

/
/
gm

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 = "(?s)(Object(?:(?!Object).)*?ByteCode[ \\t]*:[ \\t]*\\R+)((?:(?:(?!EndByteCode).)*?(?:(?(3)(?!))(\\b\\w*?z\\b)|(?(4)(?!))(?!\\3\\b)(\\b\\w*?z\\b)|(?(5)(?!))(?!\\b(?:\\3|\\4)\\b)(\\b\\w*?z\\b)|(?(6)(?!))(?!\\b(?:\\3|\\4|\\5)\\b)(\\b\\w*?z\\b)|(?(7)(?!))(?!\\b(?:\\3|\\4|\\5|\\6)\\b)(\\b\\w*?z\\b)|(?(8)(?!))(?!\\b(?:\\3|\\4|\\5|\\6|\\7)\\b)(\\b\\w*?z\\b)|(?(9)(?!))(?!\\b(?:\\3|\\4|\\5|\\6|\\7|\\8)\\b)(\\b\\w*?z\\b))){1,7})"; final String string = "BEFORE:\n\n" + " Object\n" + " Type : InfinityProgram\n" + " LastChange : 2/18/2025 5:15:38 PM\n" + " DeviceId : NetWork_MankatoO\\OfcDmp\\Vav5_26\n" + " Alias : RmTempSignalPRG\n" + " CreateTime : 2/18/2025 5:13:20 PM\n" + " CreatedBy : Root\\Acc\n" + " TimeLocked : 2/18/2025 5:15:38 PM\n" + " InstanceId : 7227/33\n" + " ByteCode :\n\n" + "'ROOM TEMPERATURE CONTROL SIGNAL CALCULATIONS ' Dylan Salisbury Paape Energy Services 5/19/23\n\n" + "Numeric sync, lasthour\n" + "Numeric actn ' control loop \"action\" 1 or 0 (direct or reverse)\n\n" + "Line StartUp\n" + " Goto RmHappy\n\n" + "Line RmHappy\n" + " If ((IntrLkSystemRun = On) & (TempRmAvg > (StptRoom + 1)) & (TS > 2)) then Goto RmWarm\n" + " TempRmCntrlSig = 50\n" + " DamperPositionz = .5\n\n\n" + "Line RmWarm\n" + " If ((IntrLkSystemRun = Off) or (TempRmAvg < StptRoom)) then Goto RmHappy\n" + " TempRmCntrlSigz = PID11Fct(TempRmAvg, StptRoom, PIDTR[1], PIDTR[2], PIDTR[3], 0.5, actn, PIDTR[4], PIDTR[5], 0.5, 1, TempRmCntrlSigz, 0.005, Date)\n" + " TempRmCntrlSig = (TempRmCntrlSigz * 100)\n" + " DamperPositionz = .25\n\n" + " TempRmCntrlSigzAAAz = XXX\n\n\n" + " EndByteCode\n" + " Status : Active\n" + " EndObject"; final String subst = "$1Numeric $3, $4, $5, $6, $7, $8, $9\\r\\n\\r\\n$2"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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