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

/
/
gx

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 = "(?<callsign>\\w+?)>APRS,.+?,\n" + "(?<receiver>\\w+):\\/\n" + "(?<time>\\d{6})h\n" + "(?<latitude>\\d{4}\\.\\d{2}[NS]).\n" + "(?<longitude>\\d{5}\\.\\d{2}[EW]).\n" + "(?:(?<heading>\\d{3})\\/(?<ground_speed>\\d{3}))?.*?\n" + "\\/A=(?<altitude>\\d{6})\\s\n" + "(?:!W((?<latitude_enhancement>\\d)(?<longitude_enhancement>\\d))!)?\n" + "(?:v(?<version>\\d+\\.\\d+\\.\\d+)(?:\\.(?<platform>.+?))?\\s)?\n" + "CPU:(?<cpu_load>[\\d.]+)\\s\n" + "RAM:(?<ram_free>[\\d.]+)\\/(?<ram_total>[\\d.]+)MB\\s\n" + "NTP:(?<ntp_offset>[\\d.]+)ms\\/(?<ntp_correction>[+-][\\d.]+)ppm\\s?\n" + "(?:(?<cpu_temperature>[+-][\\d.]+)C\\s*)?\n" + "(?:RF:\n" + " (?:\n" + " (?<manual_correction>[+-][\\d]+)\n" + " (?<automatic_correction>[+-][\\d.]+)ppm\\/\n" + " )?\n" + " (?<signal>[+-][\\d.]+)dB\n" + ")?"; final String string = "LKHS>APRS,TCPIP*,qAC,GLIDERN2:/211635h4902.45NI01429.51E&000/000/A=001689 v0.2.4.ARM CPU:0.2 RAM:777.7/972.2MB NTP:3.1ms/-3.8ppm +33.6C RF:+62-0.8ppm/+33.66dB\n\n" + "Moosburg>APRS,TCPIP*,qAC,GLIDERN1:/232205h4827.52NI01155.89E&000/000/A=001397 v0.2.4.ARM CPU:0.8 RAM:788.7/1017.6MB NTP:16000.0ms/-73.4ppm RF:+8.00dB"; final Pattern pattern = Pattern.compile(regex, Pattern.COMMENTS); 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