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 = "(https?:\\/\\/[-|\\w\\.|\\/]+)"; final String string = " <div class=\"col-sm-8\"><p>TLX is a Flat-Face twist lock coupling for the toughest applications in the construction and demolition segment. This super-duty quick connect coupling is designed to work with the highest surge flows and the toughest pressure impulses. TLX is made from high alloy steels with Zinc-Nickel surface treatment for a long life in the harshest conditions. The Series is available in sizes from ½” to 1 ½” to cover most applications.</p><br /><p>- The couplings and nipples are also available in 4 other sizes: ¾” (Series 607) 1” (Series 707) 1 ¼” (Series 807) and 1 ½ ” (Series 907) https://www.cejn.com/globalassets/documents/brochures/tlx-en.pdf</p></div>\n\n" + " <div class=\"col-sm-4\">\n" + " <img src=\"/globalassets/product/cejn/series-507/group/series-507-tlx-group-cejn.jpg?w=275\" rel=\"lightbox\" alt=\"Series 507 - &#189;”\" class=\"cboxElement\" />\n" + " </div>\n"; 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