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
Processing...

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 = "@param\\s+\\{\\(?([^\\}]+)\\)?\\}\\s+(\\[.+\\]|[\\w]+(?:\\[.+\\])?)\\s+([\\s\\S]*?)(?=\\@|\\*\\/)"; final String string = "/**\n" + " * Removes elements from \\`array\\` corresponding to \\`indexes\\` and returns an\n" + " * array of removed elements.\n" + " *\n" + " * **Note:** Unlike \\`_.at\\`, this method mutates \\`array\\`.\n" + " *\n" + " * @static\n" + " * @memberOf _\n" + " * @category Array\n" + " * @param {Array} array The array to modify.\n" + " * @param {...(number|number[])} [indexes] The indexes of elements to remove,\n" + " * specified individually or in arrays.\n" + " * @returns {Array} Returns the new array of removed elements.\n" + " * @example\n" + " *\n" + " * var array = [5, 10, 15, 20];\n" + " * var evens = _.pullAt(array, 1, 3);\n" + " *\n" + " * console.log(array);\n" + " * // => [5, 15]\n" + " *\n" + " * console.log(evens);\n" + " * // => [10, 20]\n" + " */\n" + "var pullAt = rest(function(array, indexes) {\n" + " indexes = arrayMap(baseFlatten(indexes), String);\n\n" + " var result = baseAt(array, indexes);\n" + " basePullAt(array, indexes.sort(compareAscending));\n" + " return result;\n" + "});"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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