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
Processing...

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 = "((?<=\\/23836\\*).+?(?=\\*23836\\/))|((?<=\\/23836\\/)[^*].+?[\\n])"; final String string = "#include <iostream>\n" + "#include <stdlib.h>\n\n" + "#define MAX 256\n" + "/23836//23836/Definiramo konstanto MAX\n\n" + "int main() {\n" + " /23836*Vstopna točka programa\n" + " Ne uporabljamo parametrov pri main, kjer jih ne potrebujemo\n\n" + " *23836/\n" + " printf(\"\");/23836/izpis vrednosti konstante MAX\n\n" + " return 0;\n" + "}\n" + "/23836/Končamo z izvajanjem programa\n\n" + "/23836//23836/komentar/23836/\n\n" + "/23836//23836*Testni komentar/23836/ /23836* /23836/\n\n" + "/23836*komentar/23836/nov komentar/test/23836/*23836/\n\n" + "/23836*/**Kaj pa ta vzorec?*/23836* /23836**23836/\n\n\n\n" + "(?<=\\/23836\\/).*?|(?<=\\/23836\\*)[\\S\\s]*(?=\\*23836\\/)/gmU\n" + "((?<=\\/23795\\*).+?(?=\\*23795\\/))|((?<=\\/23795\\/)[^*].+?[\\n])\n\n" + "(?<=\\/23836\\/).*$|(?<=\\/23836\\*)(.*$\\n.*\\n.*\\n.*)(?=\\*23836\\/)|(?<=\\/23836\\*)(.|\\n)*(?=\\*23836\\/)|(?<=\\/23836\\*).*(?=\\*23836\\/)"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL); 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