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

/
/

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 = "Representatives:\\s+(?<rep_name>.*)\\(.*\\)\\s+((?<rep2_name>.*)?\\s+\\()?"; final String string = "----------------------------------------------\n" + "SESSION SUMMARY\n" + "----------------------------------------------\n" + "Representatives:\n" + " Amoz Abraham (ID: 23)\n" + " Jose Sandoval (ID: 25)\n\n" + "Customer Name: [Pinned] SOUTHLAWN02\n" + "Customer's Public IP: 174.110.83.140:56969\n" + "Customer's Private IP: 10.5.65.90\n\n" + "Session Start Time: 2020-05-15 17:03:22 US/Pacific\n" + "Session End Time: 2020-05-15 17:11:37 US/Pacific\n" + "Duration: 00:08:15\n" + "# Files Transferred: 0\n" + "# Files Moved: 0\n" + "# Files Deleted: 0\n\n\n" + "----------------------------------------------\n" + "SYSTEM INFORMATION RETRIEVED\n" + "----------------------------------------------\n" + "## General ## \n" + " \n" + "Version: Windows 10 Pro x64 \n" + "Computer Name: SOUTHLAWN02 \n" + "System BIOS: \n" + "Processor 1 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Processor 2 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Processor 3 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Processor 4 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Processor 5 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Processor 6 Info: Intel(R) Core(TM) i5-9500 CPU @ 3.00GHz \n" + "Default Browser: Google Chrome \n" + "Default Browser Version: 81.0.4044.138 \n" + "Default Browser Location: C:\\Program Files (x86)\\Google\\Chrome\\Application\\chrome.exe \n" + "Windows® Directory: C:\\Windows \n" + "System Directory: C:\\Windows\\system32 \n" + "Time Zone: Eastern Daylight Time \n" + " "; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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