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 = "(?:class|href)([\\s='\"./]+)([\\w-./?=&\\\\#\"]+)((['#\\\\&?=/\".\\w\\d]+|[\\w)('-.\"\\s]+)['\"]|)"; final String string = "<a href=test.html/?v=1#subject\\login class=xyz data=\"blah\" myattr=\"example\">\n" + "<a href = test.html class=xyz data=' blah'>\n" + "<a href= \"test . html\" class=\" xyz \" data=blah>\n" + "<a href = ' ./test.html#bir/deneme/?k=1&v=1 ' class= \"a xyz_bir-ahmet. abc\">\n" + "<a href = ' ./test.html' class= 'xyz abc'>\n" + "<a href = ' .././test.html' class= 'xyz abc'>\n" + "<a href = 'test.html' class = \" xyz ui abc\">\n" + "<a href='test.html' class ='xyz ui abc'>\n" + "<a href=\"test.html\" class=\" xyz ui abc\">\n" + "<a href= \"test.html \" class=\"xyz \"data=blah>\n" + "<a href=test.html class=\"xyz \" data=blah>\n" + "<a href=test.html class=\"xyz\" data=blah>\n" + "<a href=test.html class = xyz data=\"blah\">\n" + "<meta http-equiv=\"Set-Cookie\" content=\"COOKIE2_VALUE_HERE\">"; 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