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

/
/
gsU

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*?([^>]*)\\s*(?:\\/>|>(.*)<\\/\\1>)"; final String string = " <?xml version=\"1.0\"?>\n" + " <Name attribute = \"value\" attribute2=\"value2\" >Convert number to string</Name>\n" + " <CommandLine>Examp1.EXE</CommandLine>\n" + " <Input>1</Input>\n" + " <Output>One</Output>\n" + " <Test TestId=\"0002\" TestType=\"CMD\">\n" + " <Name>Find succeeding characters</Name>\n" + " <CommandLine>Examp2.EXE</CommandLine>\n" + " <Input>abc</Input>\n" + " <Output>def</Output>\n" + " </Test>\n" + " <Test TestId=\"0003\" TestType=\"GUI\">\n" + " <Name>Convert multiple numbers to strings</Name>\n" + " <CommandLine>Examp2.EXE /Verbose</CommandLine>\n" + " <Input>123</Input>\n" + " <Output>One Two Three</Output>\n" + " </Test>\n" + " <Test TestId=\"0004\" TestType=\"GUI\">\n" + " <Name>Find correlated key</Name>\n" + " <CommandLine>Examp3.EXE</CommandLine>\n" + " <Input>a1</Input>\n" + " <Output>b1</Output>\n" + " </Test>\n" + " <Test TestId=\"0005\" TestType=\"GUI\">\n" + " <Name>Count characters</Name>\n" + " <CommandLine>FinalExamp.EXE</CommandLine>\n" + " <Input>This is a test</Input>\n" + " <Output>14</Output>\n" + " </Test>\n" + " <Test TestId=\"0006\" TestType=\"GUI\">\n" + " <Name>Another Test</Name>\n" + " <CommandLine>Examp2.EXE</CommandLine>\n" + " <Input>Test Input</Input>\n" + " <Output>10</Output>\n" + " </Test>\n" + " <Test/>\n" + " <Test />\n" + " <Test></Test>\n" + " <Test attribute = \"value\" attribute2=\"value2\"/>\n" + " <Test attribute = \"value\" attribute2=\"value2\" />\n" + " <Test attribute = \"value\" attribute2=\"value2\" ></Test>\n\n\n\n" + "<([^\\/> ]+?)\\s*?([^>]*)\\s*(?:\\/>|>(.*)<\\/\\1>) - (with g-, s- & U-modifiers) finds all tags in scope\n\n" + "1st group is tagname\n" + "2nd group is attributes\n" + "3rd group (if it exists) is value of the tag\n\n" + "Apply pattern again on 3th group to find internal tags (recurse in the code to parse entire xml!)\n\n\n" + "Apply pattern below on 2nd group to find all attributes:\n\n" + "\\s*([^<>\\=\" ]+)\\s*=\\s*\"([^\"]*)\" - (with g-modifier) finds attributes\n\n" + " 1st group is attributename\n" + " 2nd group is attributevalue"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL | Pattern.UNICODE_CHARACTER_CLASS); 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