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*(?:(?:\\S\\s?)*\\s+){2}(?:L\\d+:\\s*)?| +(?= )"; final String string = "1FC8 0801 000A BTst.B #$A, D1\n" + "1FCC 6608 BNE.B L315\n" + "1FCE 0240 00FF And #$FF, D0\n" + "1FD2 43F8 0400 Lea.L (DispatchTab), A1\n" + "1FD6 E548 L315: LsL #$2, D0\n" + "1FD8 2388 0000 Move.L A0, $0(A1,D0.W)\n" + "1FDC 7000 MoveQ.L #$0, D0\n" + "1FDE 4E75 Rts\n" + "1FE0 6102 L316: Bsr.B P42\n" + "1FE2 60F2 Bra.B L315\n\n" + " P42:\n" + "1FE4 0240 01FF And #$1FF, D0\n" + "1FE8 43F8 0C00 Lea.L (ToolDispTable), A1\n" + "1FEC 0C40 0057 Cmp #$57, D0\n" + "1FF0 6212 BHI.B L318\n" + "1FF2 670C BEQ.B L317\n" + "1FF4 0C40 004F Cmp #$4F, D0\n" + "1FF8 6306 BLS.B L317\n" + "1FFA 0C40 0054 Cmp #$54, D0\n" + "1FFE 6604 BNE.B L318\n" + "2000 43F8 0400 L317: Lea.L (DispatchTab), A1\n" + "2004 4E75 L318: Rts\n" + "2006 61DC L319: Bsr.B P42\n" + "2008 601C Bra.B L320\n\n" + " P_tGetTrapAddress:\n" + "200A 0801 0009 BTst.B #$9, D1\n" + "200E 67F6 BEQ.B L319\n" + "2010 0240 01FF And #$1FF, D0\n" + "2014 43F8 0C00 Lea.L (ToolDispTable), A1\n" + "2018 0801 000A BTst.B #$A, D1\n" + "201C 6608 BNE.B L320\n" + "201E 0240 00FF And #$FF, D0\n" + "2022 43F8 0400 Lea.L (DispatchTab), A1\n" + "2026 E548 L320: LsL #$2, D0\n" + "2028 2071 0000 Move.L $0(A1,D0.W), A0\n" + "202C 7000 MoveQ.L #$0, D0\n" + "202E 4E75 Rts"; final String subst = ""; 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