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

/
/
gm

Test String

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(\\d+)\\s+(\\S+)\\s+(\\w+)\\s+\\w+\\s+\\d*\\s+\\#\\s+\\S+\\s+(?:\\d+\\s+){2}((?!.*EMPTY\\b).+)$"; final String string = "CATALYST_TH 1\n" + "BACKPLANE A\n" + "#Slot Type Serial # Rev Num Date XptA XptB Name\n" + " 2 879-858-35 0x0109037 A 0 # 0131-0 23 24 PLFD CC\n" + " 6 879-857-01 0x0253bb0 A 0 # 9517-0 15 16 PMM CC-01\n" + " 7 000-000-00 0x0000000 P0 0 # 0000-0 13 14 EMPTY \n" + " 8 000-000-00 0x0000000 P0 0 # 0000-0 11 12 EMPTY \n" + " 9 000-000-00 0x0000000 P0 0 # 0000-0 9 10 EMPTY \n" + " 10 000-000-00 0x0000000 P0 0 # 0000-0 7 8 EMPTY \n" + " 20 000-000-00 0x0000000 P0 0 # 0000-0 37 38 EMPTY \n" + " 21 000-000-00 0x0000000 P0 0 # 0000-0 39 40 EMPTY \n" + " 22 000-000-00 0x0000000 P0 0 # 0000-0 41 42 EMPTY \n" + " 23 000-000-00 0x01a2446 P0 0 # 0000-0 43 44 EMPTY \n" + " 1 949-669-00 0x026a850 B 0 # 0809-0 3 0 HAS (Left HAS LA669-00)\n" + " 13 949-668-00 0x200762d A 0 # 9530-0 0 0 CATALYST HAC\n" + " 12 949-667-00 0x026a4ee D 0 # 0102-0 0 0 DIF\n" + " 24 949-669-01 0x2006037 B 0 # 9717-0 4 0 HAS (Right HAS LA669-01)\n" + "END"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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