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 = "intensity\\\"\\s*:\\s*\\(\\\"\\w+\\\"\\s*:\\s*(?<intensity>\\d+)"; final String string = "(\"data\": [\"from\" :\n" + "\"2024-04-25T11: 30Z\",\n" + "\"to\": \"2024-04-2512:00Z\",\n" + "\"intensity\": (\"forecast\": 152,\n" + "\"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T12:002\",\n" + "\"intensity\": {\"forecast\": 152, \"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T12:30Z\",\n" + "\"to\":\n" + "{\"from\": \"2024-04-25T13:00Z\", \"to\":\n" + "\"2024-04-25T12: 30Z\",\n" + "(\"forecast\": 164,\n" + "\"actual\": null,\n" + "\"2024-04-2513: 30Z\", \"intensity\": (\"forecast\": 154,\n" + "\"to\": \"2024-04-25T13: 002\",\n" + "\"intensity\": (\"forecast\": 154,\n" + "\"actual\": null,\n" + "\"index\":\n" + "\"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T13:30Z*, \"to\": \"2024-04-25T14:002\",\n" + "\"moderate\"}},\n" + "\"intensity\"：\n" + "04-25T14: 30Z\",\n" + "\"to\" :\n" + "\"index\": \"moderate\"3}, (\"from\": \"2024-04-25T14:002*, \"to\": \"2024-04-25T14:30Z\", \"intensity\": (\"forecast\": 166, \"actual\": null, \"index\": \"moderate\"}), (\"from\":\n" + "\" 2024-04-25T15:00Z\"\n" + "\"actual\": nu11,\n" + "\"index\"\n" + "\"intensity\": {\"forecast\": 170, \"actual\": null, \"index\": \"moderate\"}), {\"from\": \"2024-04-2515: 00Z\",\n" + "2024-\n" + "\"to\" :\n" + "\"moderate\"}), {\"from\": \"2024-04-25T15:30Z\", \"to\": \"2024-04-25T16:00Z\", \"intensity\": (\"forecast\": 175,\n" + "\"to\": \"2024-04-25T15: 30Z\",\n" + "\"intensity\": {\"forecast\": 172,\n" + "\"2024-04-25T16: 30Z\",\n" + "\"index\": \"moderate\"}}, (\"from\": \"2024-04-25T17:00Z\", \"to\":\n" + "\"intensity\": (\"forecast\": 177, \"actual\": null, \"index\": \"moderate\"?), (\"from\": \"2024-04-2516: 302\",\n" + "\"actual\" : nu11,\n" + "\"index\"\n" + "\"moderate\"}}, (\"from\": \"2024-04-2516: 00Z\",\n" + "\"to\": \"2024-04-25T17:002\",\n" + "\"intensity\": (\"forecast\": 179,\n" + "\"actual\": null,\n" + "2024-04-2517: 30Z\", \"intensity\": (\"forecast\": 181, \"actual\": null,\n" + "25T18:00Z\", \"intensity\": (\"forecast\": 184,\n" + "\"index\": \"moderate\"}}, {\"from\": \"2024-04-25T17: 30Z\",\n" + "\"actual\": null, \"index\": \"moderate\"}), (\"from\": \"2024-04-25T18:002\", \"to\": \"2024-04-25T18: 30Z\",\n" + "\"to\": \"2024-04-\n" + "\"moderate\"}}, (\"from\": \"2024-04-2518: 30Z\", \"to\": \"2024-04-25T19:002\",\n" + "\"intensity\": (\"forecast\": 187, \"actual\": null,\n" + "\"intensity\": (\"forecast\": 190,\n" + "\"actua1\": nul1,\n" + "\"index\":\n" + "\"index\":\n" + "\"high\"}}, (\"from\":\n" + "\"intensity\": {\"forecast\": 193,\n" + "\"actual\": null, \"index\":\n" + "\"2024-04-25T19: 00Z\", \"to\":\n" + "\"2024-04-25T19: 30Z\"\n" + "\"high\"}}, (\"from\": \"2024-04-25T19:30Z\", \"to\": \"2024-04-25T20:00Z\", \"intensity\":\n" + "{\"forecast\": 194,\n" + "\"2024-04-2520: 00Z\", \"to\": \"2024-04-25T20:30Z\", \"intensity\": {\"forecast\": 195, \"actual\": null, \"index\": \"high\"3}, (\"from\": \"2024-04-25T20:30Z\",\n" + "\"actual\": null, \"index\": \"high\")}, (\"from\":\n" + "\"2024-04-25T21:00Z\", \"intensity\": (\"forecast\":\n" + "198, \"actual\": null, \"index\": \"high\"'), (\"from\": \"2024-04-25T21: 002\",\n" + "\"2024-04-25T22: 00Z\", \"intensity\": {\"forecast\": 187, \"actual\": null,\n" + "\"to\": \"2024-04-25T21: 30Z\", \"intensity\": {\"forecast\": 196,\n" + "'actual\": null,\n" + "\"index\": \"high\"}}, {\"from\": \"2024-04-25T21:302\"\n" + "\"to\"\n" + "\"index\": \"moderate\"}}, (\"from\": \"2024-04-25T22:00Z\", \"to\":\n" + "\"2024-04-25T22: 30Z\",\n" + "\"intensity\": (\"forecast\": 181, \"actual\": null,\n" + "\"index\": \"moderate\"}}, {\"from\": \"2024-04-25T22:30Z\", \"to\": \"2024-04-25T23:002\", \"intensity\": (\"forecast\": 180, \"actual\": null,\n" + "\"index'\n" + "moderate\"｝｝，｛\"from\"：\n" + "25T23:30Z\", \"intensity\": {\"forecast\": 172, \"actual\": null, \"index\": \"moderate\"}}, {\"from\": \"2024-04-25T23: 30Z\",\n" + "\"2024-04-25T23:002\",\n" + "\"to\":\n" + "\" 2024-04-\n" + "\"moderate\"}}, {\"from\": \"2024-04-26T00:00Z\", \"to\": \"2024-04-2600: 30Z\", \"intensity\": (\"forecast\": 150,\n" + "\"to\": \"2024-04-2600: 00Z\",\n" + "\"intensity\": (\"forecast\": 150,\n" + "\"actual\": null,\n" + "\"index\":\n" + "\"actual\": null, \"index\": \"moderate\")}, (\"from\": \"2024-04-26T00: 302\",\n" + "\"to\": \"2024-04-26T01:00Z\"\n" + "\"intensity\": {\"forecast\": 149,\n" + "\"actual\": null,\n" + "\"index\": \"moderate\"}}, (\"from\": \"2024-04-26T01:002\",\n" + "\"to\": \"2024-04-26T01:30Z\", \"intensity\": {\"forecast\": 149,\n" + "\"actual\": null,\n" + "\"index\":\n" + "\"moderate\"}}, ..."; 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