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

/
/
g

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 = "\"SgxEpoch\":\\s*(\\\"([^0].{31}|.[^0].{30}|.{2}[^0].{29}|.{3}[^0].{28}|.{4}[^0].{27}|.{5}[^0].{26}|.{6}[^0].{25}|.{7}[^0].{24}|.{8}[^0].{23}|.{9}[^0].{22}|.{10}[^0].{21}|.{11}[^0].{20}|.{12}[^0].{19}|.{13}[^0].{18}|.{14}[^0].{17}|.{15}[^0].{16}|.{16}[^0].{15}|.{17}[^0].{14}|.{18}[^0].{13}|.{19}[^0].{12}|.{20}[^0].{11}|.{21}[^0].{10}|.{22}[^0].{9}|.{23}[^0].{8}|.{24}[^0].{7}|.{25}[^0].{6}|.{26}[^0].{5}|.{27}[^0].{4}|.{28}[^0].{3}|.{29}[^0].{2}|.{30}[^0].|.{31}[^0])\\\"|\"\")"; final String string = "\"SgxEpoch\": \"00000000000000000000000000000000\"\n" + "\"SgxEpoch\": \"00000000000000000000000000001000\"\n" + "\"SgxEpoch\": \"00000000000000000000000000000000\"\n" + "\"SgxEpoch\": \"\"\n" + "\"J8G9SQFG374OI2K4NKRPADZBERUFSZBU\"\n" + "[]$ for i in {1..30}; do echo \"\\\"SgxEpoch\\\": \\\"$(cat /dev/urandom | tr -dc 'A-Z0-9' | fold -w 32 | head -n 1)\\\"\"; done;\n" + "\"SgxEpoch\": \"RG1RLP2EVNB8HDNWH9GV4TJDB531WLXB\"\n" + "\"SgxEpoch\": \"GVHUIQCS92Y4D22AV7MVWD3T4PNSG1CA\"\n" + "\"SgxEpoch\": \"6XNYUHV542BZ641G7NR5J3TGIZ14805T\"\n" + "\"SgxEpoch\": \"WJAFO7E45QR0QVHAS9OII5LSZ2BJRRDT\"\n" + "\"SgxEpoch\": \"QSXAOKMVGZ3UT7R6K9II8W42SIKJB4CH\"\n" + "\"SgxEpoch\": \"C7HC5SMK85CSZ45OXW29D6JAHT4ZA2H7\"\n" + "\"SgxEpoch\": \"XRV62S6YQ5BM25NKK8VGIL31GRO4KAQC\"\n" + "\"SgxEpoch\": \"2ZPD3Y2U4RS5YQFKK36F6BJDTOCFK1PL\"\n" + "\"SgxEpoch\": \"I7UONV2YA6H2S245KPPQAASG801BB23A\"\n" + "\"SgxEpoch\": \"X7OXH645EYWTISMTT5P9X46PUOMA2EFW\"\n" + "\"SgxEpoch\": \"LF2ASFTRLY1Y1NQIO89G6GS3VHM7Y2YX\"\n" + "\"SgxEpoch\": \"KH0KU5213C3ET7QR99K1D1TX8N6K8JG9\"\n" + "\"SgxEpoch\": \"FOXZ8F490134F1Q9ARW5JAH50KXVC1ST\"\n" + "\"SgxEpoch\": \"BSFDYP5T9SUNAK097LEJH2JFAH1BVO10\"\n" + "\"SgxEpoch\": \"13IR5STLX3XIRA7D0XDSGWSTUPKBIUF4\"\n" + "\"SgxEpoch\": \"BTQULR3SH5C5I6I6JNVDG5OPCWZYIO21\"\n" + "\"SgxEpoch\": \"DBG0DK9R9S817XWJQU76ZS1C4NB9MH0D\"\n" + "\"SgxEpoch\": \"6KOJH14I94WGP7WIWSXSPIG0EMEZGN7B\"\n" + "\"SgxEpoch\": \"9A9XJEOQ157KMPQPXNZKUOZJBN9N1X82\"\n" + "\"SgxEpoch\": \"SQXDD61TZX0PZZI40A83B0F0WYAKJ4ED\"\n" + "\"SgxEpoch\": \"7XQ1DLU186KZ66ZTU393T0IT301UBHVY\"\n" + "\"SgxEpoch\": \"4M0M5Y5MOMG2RPC5153JXUY14B31O19P\"\n" + "\"SgxEpoch\": \"JY1HPMZYSCGGBUG0FG5TH8R4EXSE57EZ\"\n" + "\"SgxEpoch\": \"74O8E3WPY26ASOHM7E91KNV84AZ8ZNTM\"\n" + "\"SgxEpoch\": \"EOYJPEBTDDFI3T2YDFT16PZLJLOAQ0NK\"\n" + "\"SgxEpoch\": \"0BVQ6GQF3Q12SCW4GGDMCQQXBCDRBL9Z\"\n" + "\"SgxEpoch\": \"1L91SIZYM7ANWJE1TZX7U64QEMW267U1\"\n" + "\"SgxEpoch\": \"E0CUT3MIJLZECDP9VE63IO4TDVPNOBJ2\"\n" + "\"SgxEpoch\": \"KJYF7SZUSBGZDAIT5366YVQ63ECEMGQ1\"\n" + "\"SgxEpoch\": \"P4SV9WTRL0HGOEAD48K3E1ZHP1ZTRDKN\"\n" + "[]$\n"; final Pattern pattern = Pattern.compile(regex); 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