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

r"
"
gm

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 = "^\\d+(?:\\.\\d+)* .*(?:\\r?\\n(?!\\d+(?:\\.\\d+)* ).*)*"; final String string = "I.S. EN 60601-1:2006&A1:2013&AC:2014&A12:2014\n\n" + "60601-1 © IEC:2005 \n" + "60601-1 © IEC:2005\n\n" + "– 337 – \n" + "– 169 –\n\n" + "12.4.5.4 Other ME EQUIPMENT producing diagnostic or therapeutic radiation \n" + "When applicable, the MANUFACTURER shall address in the RISK MANAGEMENT PROCESS the \n" + "RISKS associated with ME EQUIPMENT producing diagnostic or therapeutic radiation other than \n" + "for diagnostic X-rays and radiotherapy (see 12.4.5.2 and 12.4.5.3). \n\n" + "Compliance is checked by inspection of the RISK MANAGEMENT FILE.\n\n" + "12.4.6 Diagnostic or therapeutic acoustic pressure \n" + "When applicable, the MANUFACTURER shall address in the RISK MANAGEMENT PROCESS the \n" + "RISKS associated with diagnostic or therapeutic acoustic pressure. \n\n" + "Compliance is checked by inspection of the RISK MANAGEMENT FILE.\n\n" + "13 * HAZARDOUS SITUATIONS and fault conditions\n\n" + "13.1 Specific HAZARDOUS SITUATIONS\n\n" + "* General \n\n" + "13.1.1 \n" + "When applying the SINGLE FAULT CONDITIONS as described in 4.7 and listed in 13.2, one at a \n" + "time, none of the HAZARDOUS SITUATIONS in 13.1.2 to 13.1.4 (inclusive) shall occur in the \n" + "ME EQUIPMENT.\n\n" + "The failure of any one component at a time, which could result in a HAZARDOUS SITUATION, is \n" + "described in 4.7. \n\n" + "* Emissions, deformation of ENCLOSURE or exceeding maximum temperature \n\n" + "13.1.2 \n" + "The following HAZARDOUS SITUATIONS shall not occur: \n" + "– emission of flames, molten metal, poisonous or ignitable substance in hazardous \n\n" + "quantities; \n\n" + "– deformation of ENCLOSURES to such an extent that compliance with 15.3.1 is impaired; \n" + "– \n\n" + "temperatures of APPLIED PARTS exceeding the allowed values identified in Table 24 when \n" + "measured as described in 11.1.3; \n" + "temperatures of ME EQUIPMENT parts that are not APPLIED PARTS but are likely to be \n" + "touched, exceeding the allowable values in Table 23 when measured and adjusted as \n" + "described in 11.1.3; \n\n" + "– \n\n" + "– exceeding the allowable values for “other components and materials” identified in Table 22 \n" + "times 1,5 minus 12,5 °C. Limits for windings are found in Table 26, Table 27 and Table 31. \n" + "In all other cases, the allowable values of Table 22 apply. \n\n" + "Temperatures shall be measured using the method described in 11.1.3. \n\n" + "The SINGLE FAULT CONDITIONS in 4.7, 8.1 b), 8.7.2 and 13.2.2, with regard to the emission of \n" + "flames, molten metal or ignitable substances, shall not be applied to parts and components \n" + "where: \n" + "– The construction or the supply circuit limits the power dissipation in SINGLE FAULT \n\n" + "CONDITION to less than 15 W or the energy dissipation to less than 900 J. "; 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