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

/
/
gm

Test String

Substitution

Processing...

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{11,14})|(?:\\d{5}\\s(?:\\d{3}\\s\\d{3}|\\d{6}))|(?:\\d{3}(?:\\s\\d{3}){3})|(?:\\d{4}\\s\\d{3}\\s\\d{3})).*$"; final String string = "This is sample. 775 657 7576 sample\n" + "Second sample line. 661-525-5366 sample 123\n" + "Third line sample 466.755.7888.\n" + "07123452670\n\n" + "07812 345 931\n\n" + "07412 123466\n\n" + "00447912345188\n\n" + "+971557017442\n\n" + "+971 557 856 832\n\n" + "0414 934 993\n\n" + "So basically, I need a regex for matching 11 digits. (07123456270)\n\n" + "Matching 5 digits, followed by space, followed by 3 digits, followed by space, followed by 3 digits. (07812 345 931)\n\n" + "Matching 5 digits, followed by space, followed by 6 digits (07412 123466)\n\n" + "Matching 14 digits (12345678901234)\n\n" + "Matching a + sign followed after with 12 digits (+971557017442)\n\n" + "Matching + followed with 3 digits, space, followed by 3 digits, space, 3 more digits (+971 557 856 832)\n\n" + "Last one, 4 digits, space, 3 digits, space, 3 digits. (0414 934 993)\n\n" + "Someone please help"; final String subst = "$1"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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