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

/
/

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 = "^\\s*(?:<\\?xml[^>]+>)?\\s*<([^>]+?)>[\\s\\S]+?<\\/\\1>\\s*?$"; final String string = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" + "<Recordings>\n" + " <Recording OVSTag=\"R00259003F89415063015030509\" Name=\"test\">\n" + " <Channel EndTC=\"15:03:59:10\" BeginTC=\"15:03:05:22\" Index=\"3\"/>\n" + " <Clip UName=\"801\" OVSTag=\"C00259003F89415063015394226\" Name=\"test_sub_1\">\n" + " <Channel OutPoint=\"15:03:20:19\" InPoint=\"15:03:05:22\" Default=\"true\" Index=\"3\"/>\n" + " <SmartEvent ID=\"b703578e-8dd1-6b72-c8c7-237132f66652\"/>\n" + " <SmartEvent ID=\"9287112f-45a6-1f43-0c28-76111b1b710f\"/>\n" + " <SmartEvent ID=\"a71c9fff-d1ae-7f89-5f1a-7a0a281f9904\"/>\n" + " </Clip>\n" + " </Recording>\n" + "</Recordings>\n" + "<SmartEvents>\n" + " <SmartEvent PageID=\"f3e9e264-3f1a-0f15-814a-cc7c535c1251\" ID=\"b703578e-8dd1-6b72-c8c7-237132f66652\" Name=\"FOUL\"/>\n" + " <SmartEvent PageID=\"bc3e8a3b-ea74-dad2-bd55-49a7d9725b83\" ID=\"9287112f-45a6-1f43-0c28-76111b1b710f\" Name=\"MESSI\"/>\n" + " <SmartEvent PageID=\"d15ed885-b68b-69db-8d76-3dc21e47d1d1\" ID=\"a71c9fff-d1ae-7f89-5f1a-7a0a281f9904\" Name=\"RAMOS\"/>\n" + "</SmartEvents>\n" + "<SmartEventPages>\n" + " <SmartEventPage ID=\"d15ed885-b68b-69db-8d76-3dc21e47d1d1\" Name=\"Real Team\"/>\n" + " <SmartEventPage ID=\"f3e9e264-3f1a-0f15-814a-cc7c535c1251\" Name=\"Action\"/>\n" + " <SmartEventPage ID=\"bc3e8a3b-ea74-dad2-bd55-49a7d9725b83\" Name=\"Barcelona Team\"/>\n" + "</SmartEventPages>"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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