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

r"
"
gm

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 = "(?s)(\\#\\d{1,})(.*?)(\\#\\d{1,})"; final String string = "#0\n" + "$dumpvars\n" + "0!\n" + "0\"\n" + "0#\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 7\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 6\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 5\n" + "b0000000000000000 $\n" + "bxxxxxxxxxxxxxxxx /\n" + "bxxxxxxxxxxxxxxxx .\n" + "bxxxxxxxxxxxxxxxx )\n" + "b0111111111111111 %\n" + "bxxxxxxxxxxxxxxxx 1\n" + "bxxxxxxxxxxxxxxxx 0\n" + "bxxxxxxxxxxxxxxxx *\n" + "b10101010101010101010101010101010 &\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx +\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ,\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 2\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx -\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 3\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx 4\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx (\n" + "bxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx '\n" + "$end\n" + "#600\n" + "1!\n" + "b0000000000000000 )\n" + "b0111111111111111 *\n" + "b10101010101010101010101010101010 +\n" + "b0000000000000000 /\n" + "b0111111111111111 1\n" + "b00000000000000000000000000000000 5\n" + "b10101010101010101010101010101010 4\n" + "b00000000000000000000000000000000 2\n" + "b00000000000000000000000000000000 3\n" + "b010101010101010101010101010101010 7\n" + "#1200\n" + "b0000010001010111 $\n" + "b0111101110101000 %\n" + "b10101100101001110100001001010001 &\n" + "0!\n" + "b10101010101010101010101010101010 ,\n" + "b00000000000000000000000000000000 -\n" + "#1800\n" + "1!\n" + "b0000010001010111 )\n" + "b0111101110101000 *\n" + "b10101100101001110100001001010001 +\n" + "b010101010101010101010101010101010 (\n" + "b010101010101010101010101010101010 '\n" + "b0000010001010111 /\n" + "b00000010001010110111101110101001 5\n" + "b0111101110101000 1\n" + "b00000010000110001010011000011000 5\n" + "b10101100101001110100001001010001 4\n" + "b010101100101001110100001001010001 7\n" + "b00000010000110001010011000011000 2\n" + "b00000010000110001010011000011000 3\n" + "b010101110101111111110100001101001 7\n" + "#2400\n" + "b0000100010101110 $\n" + "b0111011101010001 %\n" + "b10101110101000111101100111111000 &\n" + "0!\n" + "b10101100101001110100001001010001 ,\n" + "b00000010000110001010011000011000 -\n" + "#3000\n" + "1!\n" + "b0000100010101110 )\n" + "b0111011101010001 *\n" + "b10101110101000111101100111111000 +\n" + "b010101110101111111110100001101001 (\n" + "b010101110101111111110100001101001 '\n" + "b0000100010101110 /\n" + "b00000100001100010100110000110000 5\n" + "b0111011101010001 1\n" + "b00000100000010111010000100001110 5\n" + "b10101110101000111101100111111000 4\n" + "b010110000101111001000000000010000 7\n" + "b00000100000010111010000100001110 2\n" + "b00000100000010111010000100001110 3\n" + "b010110010101011110111101100000110 7\n" + "#3600\n" + "b0000110100000101 $\n" + "b0111001011111010 %\n" + "b10110000101000000111000110011111 &\n" + "0!\n" + "b10101110101000111101100111111000 ,\n" + "b00000100000010111010000100001110 -\n" + "#4200"; 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