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

/
/
gm

Test String

Substitution

Processing...

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 = "<((?!a|\\/a)[^>]*)>\\s*"; final String string = "<html>\n" + "<head>\n" + "<meta http-equiv=\\\"Content-Type\\\" content=\\\"text/html; charset=utf-8\\\">\n" + "<meta content=\\\"text/html; charset=us-ascii\\\">\n" + "<meta name=\\\"ProgId\\\" content=\\\"Word.Document\\\">\n" + "<meta name=\\\"Generator\\\" content=\\\"Microsoft Word 15\\\">\n" + "<meta name=\\\"Originator\\\" content=\\\"Microsoft Word 15\\\">\n" + "<style>\n" + "<!--\n" + "@font-face\n" + "\\t{font-family:\\\"Cambria Math\\\"}\n" + "@font-face\n" + "\\t{font-family:Calibri}\n" + "p.MsoNormal, li.MsoNormal, div.MsoNormal\n" + "\\t{margin:0cm;\n" + "\\tmargin-bottom:.0001pt;\n" + "\\tfont-size:11.0pt;\n" + "\\tfont-family:\\\"Calibri\\\",sans-serif}\n" + "a:link, span.MsoHyperlink\n" + "\\t{color:#0563C1;\n" + "\\ttext-decoration:underline}\n" + "a:visited, span.MsoHyperlinkFollowed\n" + "\\t{color:#954F72;\n" + "\\ttext-decoration:underline}\n" + "p.msonormal0, li.msonormal0, div.msonormal0\n" + "\\t{margin-right:0cm;\n" + "\\tmargin-left:0cm;\n" + "\\tfont-size:11.0pt;\n" + "\\tfont-family:\\\"Calibri\\\",sans-serif}\n" + "span.EmailStyle18\n" + "\\t{font-family:\\\"Calibri\\\",sans-serif}\n" + ".MsoChpDefault\n" + "\\t{font-size:10.0pt;\n" + "\\tfont-family:\\\"Calibri\\\",sans-serif}\n" + "@page WordSection1\n" + "\\t{margin:72.0pt 72.0pt 72.0pt 72.0pt}\n" + "div.WordSection1\n" + "\\t{}\n" + "-->\n" + "</style>\n" + "</head>\n" + "<body lang=\\\"EN-GB\\\" link=\\\"#0563C1\\\" vlink=\\\"#954F72\\\" style=\\\"\\\">\n" + "<div class=\\\"WordSection1\\\">\n" + "<p class=\\\"MsoNormal\\\">I NEED TO HAVE THIS STRING</p>\n" + "<p class=\\\"MsoNormal\\\"> </p>\n" + "<p class=\\\"MsoNormal\\\"><span style=\\\"\\\">AND I NEED THE FOLLOWING ANCHOR\n" + "<a href=\\\"google.com\\\">\n" + " THIS ONE</a>.</span></p>\n" + "<p class=\\\"MsoNormal\\\"> </p>\n" + "</div>\n" + "</body>\n" + "</html>\n"; final String subst = ""; 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