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

/
/
gm

Test String

Substitution

Processing...

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 = "^(?'id'[0-9a-fA-F]{2})(?:-(?'id_to'\\w+))? ([ \\/\\w-]+)(?: [\\/\\w]+ \\d+\\.\\d+)?$"; final String string = "00 Undefined\n" + "01 Flight Simulation Device CA 5.2\n" + "02 Automobile Simulation Device CA 5.3\n" + "03 Tank Simulation Device CA 5.4\n" + "04 Spaceship Simulation Device CA 5.2\n" + "05 Submarine Simulation Device CA 5.5\n" + "06 Sailing Simulation Device CA 5.5\n" + "07 Motorcycle Simulation Device CA 5.6\n" + "08 Sports Simulation Device CA 5.1\n" + "09 Airplane Simulation Device CA 5.2\n" + "0A Helicopter Simulation Device CA 5.2\n" + "0B Magic Carpet Simulation Device CA 5.7\n" + "0C Bicycle Simulation Device CA 5.6\n" + "0D-1F Reserved\n" + "20 Flight Control Stick CA 5.2\n" + "21 Flight Stick CA 5.2\n" + "22 Cyclic Control CP 5.2\n" + "23 Cyclic Trim CP 5.2\n" + "24 Flight Yoke CA 5.2\n" + "25 Track Control CP 5.4\n" + "26-AF Reserved\n" + "B0 Aileron DV 5.2\n" + "B1 Aileron Trim DV 5.2\n" + "B2 Anti-Torque Control DV 5.2\n" + "B3 Autopilot Enable OOC 5.2\n" + "B4 Chaff Release OSC 5.2\n" + "B5 Collective Control DV 5.2\n" + "B6 Dive Brake DV 5.2\n" + "B7 Electronic Countermeasures OOC 5.2\n" + "B8 Elevator DV 5.2\n" + "B9 Elevator Trim DV 5.2\n" + "BA Rudder DV 5.2\n" + "BB Throttle DV 5.2\n" + "BC Flight Communications OOC 5.2\n" + "BD Flare Release OSC 5.2\n" + "BE Landing Gear OOC 5.2\n" + "BF Toe Brake DV 5.2\n" + "C0 Trigger MC 5.2\n" + "C1 Weapons Arm OOC 5.2\n" + "C2 Weapons Select OSC 5.2\n" + "54\n" + "C3 Wing Flaps DV 5.2\n" + "C4 Accelerator DV 5.3\n" + "C5 Brake DV 5.3\n" + "C6 Clutch DV 5.3\n" + "C7 Shifter DV 5.3\n" + "C8 Steering DV 5.3\n" + "C9 Turret Direction DV 5.4\n" + "CA Barrel Elevation DV 5.4\n" + "CB Dive Plane DV 5.5\n" + "CC Ballast DV 5.5\n" + "CD Bicycle Crank DV 5.6\n" + "CE Handle Bars DV 5.6\n" + "CF Front Brake DV 5.6\n" + "D0 Rear Brake DV 5.6\n" + "D1-FFFF Reserved\n"; final String subst = "\\t${id_to:+// 0x${id}-0x${id_to} $3:${name} = 0x${id},}"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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