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

/
/
gmi

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+\\s?\\D+)\\s?(\\d+[,\\d+]*)\\s?(\\d+[,\\d+]*)\\s?(\\d+[,\\d+]*)\\s?(\\d+[,\\d+]*)\\s?(\\d+[,\\d+]*)\\s?"; final String string = "Weapon Type/Force Used 2000 2001 2002 2003 2004 5-Year Total\n" + "Personal Weapons 12,945 17,830 20,636 21,933 25,050 98,394\n" + "None 2,702 3,114 2,974 3,294 4,176 16,260\n" + "Other 1,775 2,311 2,332 2,420 2,842 11,680\n" + "Knife/Cutting Instrument 1,511 2,082 2,080 2,445 2,852 10,970\n" + "Handgun 307 376 398 430 497 2,008\n" + "Blunt Object 283 404 394 455 469 2,005\n" + "Firearm (type not stated) 94 131 103 135 146 609\n" + "Other Firearm 74 107 92 155 154 582\n" + "Explosives 145 139 93 89 95 561\n" + "Motor Vehicle 43 52 46 59 71 271\n" + "Fire/Incendiary Device 36 34 42 36 88 236\n" + "Rifle 23 33 33 24 37 150\n" + "Shotgun 15 24 30 19 24 112\n" + "Drugs/Narcotics/Sleeping Pills 9 4 8 14 6 41\n" + "Poison 1 8 4 11 16 40\n" + "Asphyxiation 2 1 3 6 2 14\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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