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

Substitution

Processing...

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 = "^(.+)(\\[ *)(\\d+)(\\] *)(.+ )(.+)$"; final String string = "DIN[ 1] ON DCS_SpeedSafe\n" + "DIN[ 201] ON *IMSTP\n" + "DIN[ 202] ON *HOLD\n" + "DIN[ 203] ON SFSPD\n" + "DIN[ 204] OFF CSTOPI\n" + "DIN[ 205] OFF FAULT RESET\n" + "DIN[ 206] OFF START\n" + "DIN[ 207] OFF HOME\n" + "DIN[ 208] ON ENBL\n" + "DIN[ 209] OFF RSR1\n" + "DIN[ 210] OFF RSR2\n" + "DIN[ 211] OFF RSR3\n" + "DIN[ 212] OFF RSR4\n" + "DIN[ 213] OFF RSR5\n" + "DIN[ 214] OFF RSR6\n" + "DIN[ 215] OFF RSR7\n" + "DIN[ 216] OFF RSR8\n" + "DIN[ 219] OFF SempreOff\n" + "DIN[ 220] OFF Abilita Ciclo\n" + "DIN[ 221] OFF Abilitazione generale\n" + "DIN[ 225] OFF CaricoOk\n" + "DIN[ 226] OFF CarFuoriIngombro\n" + "DIN[ 227] OFF TraslOK\n" + "DIN[ 228] OFF TraslFuoriIngombro\n" + "DIN[ 229] OFF PezPresNastroCarico\n" + "DIN[ 230] OFF FtControlloSagoma1\n" + "DIN[ 231] OFF FtControlloSagoma2\n" + "DIN[ 232] OFF TipSagoma1\n" + "DIN[ 233] OFF TipSagoma2\n" + "DIN[ 234] OFF TavRqDepo1\n" + "DIN[ 235] OFF TavRqScambio1\n" + "DIN[ 236] OFF TavRqPrel1\n" + "DIN[ 237] OFF TavPezScarto\n" + "DIN[ 238] OFF TavFuoriImgombro\n" + "DIN[ 239] OFF TavInclusa\n" + "DIN[ 240] OFF PrelievoNastroCarico\n" + "DIN[ 241] OFF PrelievoTavola\n" + "DIN[ 242] OFF ScartoCtrlUsura\n" + "DIN[ 243] OFF TavPezPres1\n" + "DIN[ 244] OFF TavPezPres2\n" + "DIN[ 245] OFF Ctrl Ft Enable\n" + "DIN[ 246] OFF TavRqDepo2\n" + "DIN[ 247] OFF TavRqScambio2\n" + "DIN[ 248] OFF TavRqPrel2\n" + "DIN[ 249] OFF NastroAbil\n" + "DIN[ 250] OFF Carico2Ok\n" + "DIN[ 251] OFF Car2FuoriIng\n" + "DIN[ 252] OFF PezPresNastro2\n" + "DIN[ 253] OFF Nastro2Abil\n" + "DIN[ 254] OFF PriorAltern/Nas2\n" + "DIN[ 255] OFF DemoOffsEsegui\n" + "DIN[ 256] OFF DemoOffsAddOffs\n" + "DIN[ 257] OFF EnbCtrlSmussi\n" + "DIN[ 258] OFF CtrlSmussiRisKo\n" + "DIN[ 259] OFF CtrlSmussiRisOk\n" + "DIN[ 260] OFF EnbCtrlColore\n" + "DIN[ 261] OFF CtrlColoreRisKo\n" + "DIN[ 262] OFF CtrlColoreRisOk\n" + "DIN[ 263] OFF CassScartoPres\n" + "DIN[ 265] OFF Prel1_StopRq\n" + "DIN[ 266] OFF Prel2_StopRq\n" + "DIN[ 267] OFF DepoTrasl_StopRq\n" + "DIN[ 268] OFF DepoTav1_StopRq\n" + "DIN[ 269] OFF DepoTav2_StopRq\n" + "DIN[ 270] OFF CtrlSmus_StopRq\n" + "DIN[ 273] OFF Magnet_A\n" + "DIN[ 274] OFF Smagnet_A\n" + "DIN[ 275] OFF Magnet_B\n" + "DIN[ 276] OFF Smagnet_B\n" + "DIN[ 277] OFF SoffioA\n" + "DIN[ 278] OFF SoffioB\n" + "DOUT[ 201] OFF CMDENBL\n" + "DOUT[ 202] ON SYSRDY\n" + "DOUT[ 203] OFF PROGRUN\n" + "DOUT[ 204] OFF PAUSED\n" + "DOUT[ 205] OFF HELD\n" + "DOUT[ 206] OFF FAULT\n" + "DOUT[ 207] ON ATPERCH\n" + "DOUT[ 208] OFF TPENBL\n" + "DOUT[ 209] OFF BATALM\n" + "DOUT[ 210] OFF BUSY\n" + "DOUT[ 211] OFF ACK1\n" + "DOUT[ 212] OFF ACK2\n" + "DOUT[ 213] OFF ACK3\n" + "DOUT[ 214] OFF ACK4\n" + "DOUT[ 215] OFF ACK5\n" + "DOUT[ 216] OFF ACK6\n" + "DOUT[ 217] OFF NumProgErr\n" + "DOUT[ 218] ON InHome\n" + "DOUT[ 219] OFF InManut\n" + "DOUT[ 220] OFF InRiscaldamento\n" + "DOUT[ 221] OFF InPulizPz\n" + "DOUT[ 222] OFF InCheckFt\n" + "DOUT[ 223] OFF SegnaliSimulati\n" + "DOUT[ 224] OFF Modo T1 Attivo\n" + "DOUT[ 233] OFF CicloRiposo(Tappa0)\n" + "DOUT[ 234] OFF PezPrelNastroCarico\n" + "DOUT[ 235] OFF CicloNastroCarico\n" + "DOUT[ 236] ON NastroCaricoFuoriIng\n" + "DOUT[ 237] OFF PezDepTrasl\n" + "DOUT[ 238] OFF CicloTrasl\n" + "DOUT[ 239] ON TraslFuoriIng\n" + "DOUT[ 240] OFF PezScarto\n" + "DOUT[ 241] OFF PzNoPrelNastroCarico\n" + "DOUT[ 242] OFF TavPezDep1\n" + "DOUT[ 243] OFF TavPezScambio1 \n" + "DOUT[ 244] OFF TavPezPrel1\n" + "DOUT[ 245] ON TavFuoriIng\n" + "DOUT[ 246] OFF CicloTav\n" + "DOUT[ 247] OFF TavPezNoPrel1\n" + "DOUT[ 248] OFF TavPezNoPrel2\n" + "DOUT[ 249] OFF TavPezDep2\n" + "DOUT[ 250] OFF TavPezScambio2\n" + "DOUT[ 251] OFF TavPezPrel2\n" + "DOUT[ 252] OFF PezPrelNastro2\n" + "DOUT[ 253] OFF CicloNastro2\n" + "DOUT[ 254] OFF FuoriIngNastro2\n" + "DOUT[ 255] OFF PezNoPrelNas2\n" + "DOUT[ 256] OFF DemoOfsPosOk\n" + "DOUT[ 257] OFF PosCtrlSmussi\n" + "DOUT[ 258] OFF PosCtrlColore\n" + "DOUT[ 259] ON FuoriIngCtrlSmus\n" + "DOUT[ 260] ON FuoriIngProfil\n" + "DOUT[ 267] OFF MagneteAAttira\n" + "DOUT[ 268] OFF MagnateARilascia\n" + "DOUT[ 269] OFF MagneteBAttira\n" + "DOUT[ 270] OFF MagneteBRilascia\n" + "DOUT[ 273] OFF Prel1_Stop\n" + "DOUT[ 274] OFF Prel2_Stop\n" + "DOUT[ 275] OFF DepoTrasl_Stop\n" + "DOUT[ 276] OFF DepoTav1_Stop\n" + "DOUT[ 277] OFF DepoTav2_Stop\n" + "DOUT[ 278] OFF CtrlSmus_Stop\n" + "GIN[ 1] 0 NumProg\n" + "GIN[ 2] 0 VelCiclo\n" + "GIN[ 3] 0 CodPastiglia\n" + "GIN[ 4] 0 Offset X\n" + "GIN[ 5] 0 Offset Y\n" + "GIN[ 6] 0 Offset Z\n" + "GIN[ 7] 0 Offset rotaz X\n" + "GIN[ 8] 0 Offset rotaz Y\n" + "GIN[ 9] 0 Offset rotaz Z\n" + "GIN[ 15] 0 CmdMan\n" + "GOUT[ 1] 0 NumeroProgAttivo\n" + "GOUT[ 2] 0 ComandoEseguito\n" + "GOUT[ 3] 0 DemoOffsNumPos\n" + "UI[ 1] ON *IMSTP\n" + "UI[ 2] ON *Hold\n" + "UI[ 3] ON *SFSPD\n" + "UI[ 4] OFF Cycle stop\n" + "UI[ 5] OFF Fault reset\n" + "UI[ 6] OFF Start\n" + "UI[ 7] OFF Home\n" + "UI[ 8] ON Enable\n" + "UI[ 9] OFF Rsr0001\n" + "UI[ 10] OFF RSR2/PNS2/STYLE2\n" + "UI[ 11] OFF RSR3/PNS3/STYLE3\n" + "UI[ 12] OFF RSR4/PNS4/STYLE4\n" + "UI[ 13] OFF RSR5/PNS5/STYLE5\n" + "UI[ 14] OFF RSR6/PNS6/STYLE6\n" + "UI[ 15] OFF RSR7/PNS7/STYLE7\n" + "UI[ 16] OFF RSR8/PNS8/STYLE8\n" + "UO[ 1] OFF Cmd enabled\n" + "UO[ 2] ON System ready\n" + "UO[ 3] OFF Prg running\n" + "UO[ 4] OFF Prg paused\n" + "UO[ 5] OFF Motion held\n" + "UO[ 6] OFF Fault\n" + "UO[ 7] ON At perch\n" + "UO[ 8] OFF TP enabled\n" + "UO[ 9] OFF Batt alarm\n" + "UO[ 10] OFF Busy\n" + "UO[ 11] OFF ACK1/SNO1\n" + "UO[ 12] OFF ACK2/SNO2\n" + "UO[ 13] OFF ACK3/SNO3\n" + "UO[ 14] OFF ACK4/SNO4\n" + "UO[ 15] OFF ACK5/SNO5\n" + "UO[ 16] OFF ACK6/SNO6\n" + "SI[ 1] OFF Fault reset\n" + "SI[ 2] ON Remote\n" + "SI[ 3] ON Hold\n" + "SI[ 4] OFF User PB#1\n" + "SI[ 5] OFF User PB#2\n" + "SI[ 6] OFF Cycle start\n" + "SI[ 8] ON CE/CR Select b0\n" + "SI[ 9] ON CE/CR Select b1\n" + "SO[ 1] OFF Cycle start\n" + "SO[ 2] OFF Hold\n" + "SO[ 3] OFF Fault LED\n" + "SO[ 4] OFF Batt alarm\n" + "SO[ 5] OFF User LED#1\n" + "SO[ 6] OFF User LED#2\n" + "SO[ 7] OFF TP enabled\n" + "RO[ 1] OFF SoffioA\n" + "RO[ 2] OFF SoffioB\n" + "FLG[ 1] OFF DCS_SpeedSafeMem\n" + "FLG[ 2] OFF Simula\n" + "FLG[ 3] OFF RemoteOverDsb\n"; final String subst = "\\1 \\t \\3 \\t \\6"; 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