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

/
/
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 = "^([^,]*,){39}\""; final String string = ",1414,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,\"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A\",\"5:39265338\",,1473800029,\"2016-09-13 20:54:20.206 +0000 Tag=\"\"MODBUS.ROBOT.Position_Base\"\" Value=\"\"1414\"\" Quality=\"\"good\"\" \",\"RS5c\n" + "kepware\",Kepware,\".206\",\"1473800060.206\",,,20,13,54,september,20,tuesday,2016,0,,,\"24.97.250.66\",kepware,1,,,\"--_::._+_=\"\"..\"\"_=\"\"\"\"_=\"\"\"\"_\",,Kepware,Kepware,RS5c,,,,,,29,0,,\n" + ",,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,\"1487.42566\",,\"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A\",\"5:39143140\",,1473798904,\"2016-09-13 20:35:35.147 +0000 Tag=\"\"OmronCJ.PLC1.Suply_conv.Belt_speed\"\" Value=\"\"1487.42566\"\" Quality=\"\"good\"\" \",\"RS5c\n" + "kepware\",Kepware,\".147\",\"1473798935.147\",,,20,13,35,september,35,tuesday,2016,0,,,\"24.97.250.66\",kepware,1,,,\"--_::._+_=\"\"...\"\"_=\"\".\"\"_=\"\"\"\"_\",,Kepware,Kepware,RS5c,,,,,,29,0,,\n" + ",,,,,,,,,,,,,,,,,,,,,0,,,,,,,,,,,,,,\"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A\",\"5:39117933\",,1473798672,\"2016-09-13 20:31:42.457 +0000 Tag=\"\"MODBUS.ROBOT.Velocity_Sholder\"\" Value=\"\"0\"\" Quality=\"\"good\"\" \",\"RS5cSplunk1\n" + "kepware\",Kepware,\".457\",\"1473798702.457\",,,20,13,31,september,42,tuesday,2016,0,,,\"24.97.250.66\",kepware,1,,,\"--_::._+_=\"\"..\"\"_=\"\"\"\"_=\"\"\"\"_\",,Kepware,Kepware,RS5c,,,,,,29,0,,\n" + ",,,,,,,,,,,,,,,,,,,,,,,,,\"1491.82166\",,,,,,,,,,\"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A\",\"5:39105700\",,1473798560,\"2016-09-13 20:29:50.387 +0000 Tag=\"\"OmronCJ.PLC1.Assy_conv.belt_speed\"\" Value=\"\"1491.82166\"\" Quality=\"\"good\"\" \",\"RS5c\n" + "kepware\",Kepware,\".387\",\"1473798590.387\",,,20,13,29,september,50,tuesday,2016,0,,,\"24.97.250.66\",kepware,1,,,\"--_::._+_=\"\"...\"\"_=\"\".\"\"_=\"\"\"\"_\",,Kepware,Kepware,RS5c,,,,,,29,0,,\n" + ",,,,,,,,,,,,,,,,,,,,1605,,,,,,,,,,,,,,,\"kepware~5~63CC97F2-5494-43F2-9F92-79A2BEF58D2A\",\"5:39087971\",,1473798396,\"2016-09-13 20:27:06.649 +0000 Tag=\"\"MODBUS.ROBOT.Velocity_Max_Wrst3\"\" Value=\"\"1605\"\" Quality=\"\"good\"\" \",\"RS5c\n\n"; 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