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

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 = "^\\s*($|#|\\w+\\s*=|(\\?|\\*|(?:[0-5]?\\d)(?:(?:-|\\/|\\,)(?:[0-5]?\\d))?(?:,(?:[0-5]?\\d)(?:(?:-|\\/|\\,)(?:[0-5]?\\d))?)*)\\s+(\\?|\\*|(?:[0-5]?(?:\\d|\\*))(?:(?:-|\\/|\\,)(?:[0-5]?\\d))?(?:,(?:[0-5]?\\d)(?:(?:-|\\/|\\,)(?:[0-5]?\\d))?)*)\\s+(\\?|\\*|(?:[01]?(?:\\d|\\*)|2[0-3])(?:(?:-|\\/|\\,)(?:[01]?\\d|2[0-3]))?(?:,(?:[01]?\\d|2[0-3])(?:(?:-|\\/|\\,)(?:[01]?\\d|2[0-3]))?)*)\\s+(\\?|\\*|(?:0?[1-9]|[12]\\d|3[01]|\\*)(?:(?:-|\\/|\\,)(?:0?[1-9]|[12]\\d|3[01]))?(?:,(?:0?[1-9]|[12]\\d|3[01])(?:(?:-|\\/|\\,)(?:0?[1-9]|[12]\\d|3[01]))?)*|(?:L)|(?:LW)|(?:L-(?:[0-9]|1\\d|2\\d|30))|(?:\\dW|1\\dW))\\s+(\\?|\\*|(?:[1-9]|1[012])(?:(?:-|\\/|\\,)(?:[1-9]|1[012]))?(?:L|W)?(?:,(?:[1-9]|1[012])(?:(?:-|\\/|\\,)(?:[1-9]|1[012]))?(?:L|W)?)*|\\?|\\*|(?:JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(?:(?:-)(?:JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?(?:,(?:JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC)(?:(?:-)(?:JAN|FEB|MAR|APR|MAY|JUN|JUL|AUG|SEP|OCT|NOV|DEC))?)*)\\s+(\\?|\\*|(?:[1-7])(?:(?:-|\\/|\\,|#)(?:[1-7]))?(?:L)?(?:,(?:[1-7])(?:(?:-|\\/|\\,|#)(?:[1-7]))?(?:L)?)*|\\?|\\*|(?:MON|TUE|WED|THU|FRI|SAT|SUN)(?:(?:-)(?:MON|TUE|WED|THU|FRI|SAT|SUN))?(?:,(?:MON|TUE|WED|THU|FRI|SAT|SUN)(?:(?:-)(?:MON|TUE|WED|THU|FRI|SAT|SUN))?)*)(|\\s)+(\\?|\\*|(?:|\\d{4})(?:(?:-|\\/|\\,)(?:|\\d{4}))?(?:,(?:|\\d{4})(?:(?:-|\\/|\\,)(?:|\\d{4}))?)*))$"; final String string = "* * * ? * *\n" + "0 0/1 * * * ?\n" + "0/5 14,18,3-39,52 * ? JAN,MAR,SEP MON-FRI 2002-2010\n" + "0 * * ? * *\n" + "0 */2 * ? * *\n" + "0 1/2 * ? * *\n" + "0 */3 * ? * *\n" + "0 */4 * ? * *\n" + "0 */5 * ? * *\n" + "0 */10 * ? * *\n" + "0 */15 * ? * *\n" + "0 */30 * ? * *\n" + "0 15,30,45 * ? * *\n" + "0 0 * ? * *\n" + "0 0 */2 ? * *\n" + "0 0 0/2 ? * *\n" + "0 0 1/2 ? * *\n" + "0 0 */3 ? * *\n" + "0 0 */4 ? * *\n" + "0 0 */6 ? * *\n" + "0 0 */8 ? * *\n" + "0 0 */12 ? * *\n" + "0 0 0 * * ?\n" + "0 0 1 * * ?\n" + "0 0 6 * * ?\n" + "0 0 12 * * ?\n" + "0 0 12 ? * SUN\n" + "0 0 12 ? * MON\n" + "0 0 12 ? * TUE\n" + "0 0 12 ? * WED\n" + "0 0 12 ? * THU\n" + "0 0 12 ? * FRI\n" + "0 0 12 ? * SAT\n" + "0 0 12 ? * MON-FRI\n" + "0 0 12 ? * SUN,SAT\n" + "0 0 12 */7 * ?\n" + "0 0 12 1 * ?\n" + "0 0 12 2 * ?\n" + "0 0 12 15 * ?\n" + "0 0 12 1/2 * ?\n" + "0 0 12 1/4 * ?\n" + "0 0 12 L * ?\n" + "0 0 12 L-2 * ?\n" + "0 0 12 L-12 * ?\n" + "0 0 12 L-22 * ?\n" + "0 0 12 L-30 * ?\n" + "0 0 12 LW * ?\n" + "0 0 12 1W * ?\n" + "0 0 12 15W * ?\n" + "0 0 12 ? * 2#1\n" + "0 0 12 ? * 6#1\n" + "0 0 12 ? * 2#2\n" + "0 0 12 ? * 5#3\n" + "0 0 12 ? JAN *\n" + "0 0 12 ? JUN *\n" + "0 0 12 ? JAN,JUN *\n" + "0 0 12 ? DEC *\n" + "0 0 12 ? JAN,FEB,MAR,APR *\n" + "0 0 12 ? 9-12 *\n" + "0 1 0 ? * 7\n" + "0 59 23 ? * 7,2,1,5"; 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