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 = "(?P<monitor_IO_Elem>^(?P<placeId_IO_Elem>(?:\\d{1,2}.\\w{1,2}))(?:\\ *)(?P<Id_IO_Elem>(?:S|L|P|cvM|vM|V)(?:\\d{1,2})(?:\\ *)(?:-?)(?:\\ *)(?:\\d{1,2}))(?:\\ )* (?:\\-)* (?:\\ )*(?:\\[)(?P<seqNrPin__IO_Elem>(?:\\d){1,2})(?:\\])(?:\\ *)(?P<action>(?:S|D|T|L|ON|OFF))$)(?:[\\n|\\r])?"; final String string = "T203_AL2\n" + "T203\n" + "T202 PV - slaapkamer 2\n" + "T202 CV - slaapkamer 2\n" + "1.1 S3-8 - mode 6\n" + "1.1 S3-8 - [1] S\n" + "1.1 S3-8 - [3] D\n" + "1.3 S5-10 - mode !DEFAULT [shift]\n" + "1.3 S5-10 - [2] D\n" + "I/O 0.4 D1_[AUTO : TM s]\n" + "I/O 0.4 D1_[AUTO : TM l]\n" + "I/O 0.4 D1_[AUTO]\n" + "I/O 1.1 S3-8_[6]_LED -2-\n" + "I/O 1.1 S3-8_[2] -1-\n" + "#EXTRA INFO REFERENCE for I/O 2.4 S1-4_[4] --- NAME : I/O 2.4 S1-4_[4] -4- --- INFO : K21 [08 I]\n" + "#EXTRA INFO REFERENCE for 2.4 S5-8 --- NAME : 2.4 S5-8 - mode DEFAULT --- INFO : 2.4 S5-8 [K22] / 4x + LED\n" + "2.4 S5-8 [K22] / 4x + LED\n" + "# HUIS CONTACT\n" + "HC_1.1_1.2_1.3_1.4\n\n" + "-1- 0.2 cvM1\n" + "-1- 1.6 vM2 [speed !MIN/MAX]\n" + "-1- 1.1 L6/L7/L8 (3 x spots - plafond)\n" + "-1- 1.B3 L1/L2 (grondspots voordeur)\n" + "-2- 2.7 V2 SSR1\n" + "002 - 0.2 kelder 2\n" + "003 - 0.3 kelder 3 [nutsvoorziening]\n" + "110 - 1.# SSR\n" + "B04 - 1.B SSR (all)\n" + "[F2401] K3 - Q5 : 2.B1 terras slaapkamer\n" + "[F2308] K3 - Q3 : 2.7 KAST V2 PWR SUPPLY SSR [Nyah-logeer-Caelan]\n" + "[F1612] K1 - Q1 : 1.9 WC ventilator [10.R1] R501\n" + "mode : 1.1 KEUKEN\n" + "[F1613] K2 - Q1 : 0.2 KELDER CV - [10.R09] R509 + rad lev 0 & 1"; 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