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 = "((8|\\+7?)[\\- ]?)?(\\(?\\d{3}\\)?[\\- ]?)?([\\d\\- ]{7,10})"; final String string = "======== local phone\n\n" + "765-43-21\n" + "7654321\n" + "765-4321\n\n" + "======== operator phone\n\n" + "(921) 765-43-21\n" + "(921) 7654321\n" + "(921) 765-4321\n\n" + "(921)765-43-21\n" + "(921)7654321\n" + "(921)765-4321\n\n" + "921765-43-21\n" + "9217654321\n" + "921765-4321\n\n" + "921-765-43-21\n" + "921-7654321\n" + "921-765-4321\n\n" + "======== world phone\n\n" + "+7 (921) 765-43-21\n" + "+7(921) 765-43-21\n" + "+7-(921) 765-43-21\n" + "7 (921) 765-43-21\n" + "7(921) 765-43-21\n" + "8 (921) 765-43-21\n" + "8(921) 765-43-21\n" + "8-(921) 765-43-21\n" + "8 (921) 765-43-21\n" + "8(921) 765-43-21\n" + "8-(921) 765-43-21\n\n" + "+7 9217654321\n" + "+79217654321\n" + "+7-9217654321\n" + "7 9217654321\n" + "79217654321\n" + "7-9217654321\n" + "8 9217654321\n" + "89217654321\n" + "8-9217654321\n" + "8 9217654321\n" + "89217654321\n" + "8-9217654321\n\n" + "======== not found \n\n" + ">>>>>>>>> 1. Коржев Артём Борисович 8-921-641-82-15;\n\n" + "======== bad\n\n\n" + "0 0 0 0\n" + "333 000\n" + "1 1 1205 1320 321\n\n\n" + "======== разбор\n\n" + " # world phone\n" + " (\n" + " (8|\\+?7)\n" + " [\\- ]?\n" + " )?\n\n" + " # operator phone\n" + " (\n" + " \\(?\n" + " \\d{3}\n" + " \\)?\n" + " [\\- ]?\n" + " )?\n\n" + " # local phone\n" + " [\\d\\- ]{7,10}"; 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