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

/
/
.style

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 = "<!--block:(.*?)-->((?:(?:(?!<!--(.*?)-->).)|(?R))*?)<!--endblock-->"; final String string = "<!DOCTYPE html><html><head><title>Crew Watch (Responses)</title>\n" + "<link href='/static/spreadsheets2/client/css/461985016-waffle_k_ltr.css' type='text/css' rel='stylesheet'><style type=\"text/css\">\n" + " html { overflow: visible; }\n" + " #sheets-viewport { overflow: auto; }\n" + " #sheets-viewport.widget-viewport { overflow: hidden; }\n" + " .grid-container { overflow: visible; background: white;}\n" + " .grid-table-container { overflow: visible; }\n" + " #top-bar {\n" + " background: url(\"//ssl.gstatic.com/docs/spreadsheets/publishheader.png\") repeat-x bottom;\n" + " margin: 0;\n" + " overflow: hidden;\n" + " }\n" + " #top-bar {\n" + " border-bottom: 1px solid #ccc;\n" + " padding: 6px 6px 0;\n" + " }\n" + " #doc-title { padding-bottom: 5px; }\n" + " #doc-title .name { font-size: 15px; }\n" + " #sheet-menu {\n" + " font-size: 13px;\n" + " margin: 6px 0 0;\n" + " padding: 0 0 5px;\n" + " }\n" + " #sheet-menu li {\n" + " display: inline;\n" + " list-style-type: none;\n" + " margin: 0;\n" + " padding: 5px 8px;\n" + " }\n" + " #sheet-menu li.active {\n" + " background-color: #fff;\n" + " font-weight: bold;\n" + " border: 1px solid #999;\n" + " }\n" + " #top-bar #sheet-menu li.active {\n" + " border-bottom: 0;\n" + " }\n" + " #sheet-menu a, #sheet-menu a:visited { color: #07c; }\n" + " .ritz .waffle .s0{text-align:left;color:#000000;background-color:#ffffff;font-family:arial,sans,sans-serif;font-size:10pt;vertical-align:bottom;white-space:nowrap;direction:ltr;padding:2px 3px 2px 3px;}.ritz .waffle .s1{text-align:right;color:#000000;background-color:#ffffff;font-family:arial,sans,sans-serif;font-size:10pt;vertical-align:bottom;white-space:nowrap;direction:ltr;padding:2px 3px 2px 3px;}</style><script type=\"text/javascript\">\n" + " var activeSheetId;\n\n" + " function switchToSheet(id) {\n" + " if (document.getElementById('sheet-menu')) {\n" + " document.getElementById('sheet-button-' + activeSheetId)\n" + " .className = '';\n" + " document.getElementById('sheet-button-' + id).className = 'active';\n" + " }\n\n" + " document.getElementById(activeSheetId).style.display = 'none';\n" + " document.getElementById(id).style.display = '';\n" + " activeSheetId = id;\n\n" + " // posObjs() is defined in embeddedObjectJs (see EmbeddedObjectHtmlBuilder.java)\n" + " posObjs();\n" + " return false;\n" + " }\n" + " \n" + " function init() {\n" + " var optPageSwitcher;\n" + " \n" + " function resize() {\n" + " var optTopBar = document.getElementById('top-bar');\n" + " var adjustedHeight = window.innerHeight - (optTopBar ? optTopBar.offsetHeight : 0);\n" + " var adjustedWidth = window.innerWidth;\n" + " var sheetsViewport = document.getElementById('sheets-viewport');\n" + " sheetsViewport.style.width = (adjustedWidth + 'px');\n" + " sheetsViewport.style.height = (adjustedHeight + 'px');\n" + " if (optPageSwitcher) {\n" + " optPageSwitcher.resize(adjustedWidth, adjustedHeight);\n" + " }\n" + " }\n" + " resize();\n" + " window.onresize = resize;\n" + " }\n" + " </script></head><body onload=init()><div id=\"top-bar\"><div id=\"doc-title\"><span class=\"name\">Crew Watch (Responses) : Form Responses 1</span></div></div><div id=\"sheets-viewport\"><div id=\"1416730418\" style=\"display:none;position:relative;\" dir=\"ltr\"><div class=\"ritz grid-container\" dir=\"ltr\"><table class=\"waffle\" cellspacing=\"0\" cellpadding=\"0\"><thead><tr><th class=\"row-header freezebar-vertical-handle header-shim row-header-shim\"></th><th id=\"1416730418C0\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C1\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C2\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C3\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C4\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C5\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C6\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C7\" style=\"width:150px\" class=\"header-shim\"></th><th id=\"1416730418C8\" style=\"width:150px\" class=\"header-shim\"></th></tr></thead><tbody><tr style='height:21px;'><th id=\"1416730418R0\" style=\"height: 21px;\" class=\"row-headers-background row-header-shim\"><div class=\"row-header-wrapper\" style=\"line-height: 21px;\">1</div></th><td class=\"s0\">Timestamp</td><td class=\"s0\">First Name</td><td class=\"s0\">Middle Name</td><td class=\"s0\">Last Name</td><td class=\"s0\">Date of Birth</td><td class=\"s0\">Street Address</td><td class=\"s0\">City</td><td class=\"s0\">State</td><td class=\"s0\">Zip Code</td></tr><tr><th style=\"height:4px\" class=\"freezebar-cell freezebar-horizontal-handle row-header-shim\"></th><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td><td class=\"freezebar-cell\"></td></tr><tr style='height:21px;'><th id=\"1416730418R1\" style=\"height: 21px;\" class=\"row-headers-background row-header-shim\"><div class=\"row-header-wrapper\" style=\"line-height: 21px;\">2</div></th><td class=\"s1\" dir=\"ltr\">3/26/2014 21:33:20</td><td class=\"s0\" dir=\"ltr\">John</td><td class=\"s0\" dir=\"ltr\">Collier</td><td class=\"s0\" dir=\"ltr\">Armstrong</td><td></td><td></td><td></td><td></td><td></td></tr><tr style='height:21px;'><th id=\"1416730418R2\" style=\"height: 21px;\" class=\"row-headers-background row-header-shim\"><div class=\"row-header-wrapper\" style=\"line-height: 21px;\">3</div></th><td class=\"s1\" dir=\"ltr\">8/21/2014 0:56:02</td><td class=\"s0\" dir=\"ltr\">john</td><td class=\"s0\" dir=\"ltr\">collier</td><td class=\"s0\" dir=\"ltr\">armstrong</td><td class=\"s1\" dir=\"ltr\">1/10/1984</td><td class=\"s0\" dir=\"ltr\">4720 SW 21st St.</td><td class=\"s0\" dir=\"ltr\">Topeka</td><td></td><td class=\"s1\" dir=\"ltr\">66604</td></tr><tr style='height:21px;'><th id=\"1416730418R3\" style=\"height: 21px;\" class=\"row-headers-background row-header-shim\"><div class=\"row-header-wrapper\" style=\"line-height: 21px;\">4</div></th><td class=\"s1\" dir=\"ltr\">9/11/2014 0:56:28</td><td class=\"s0\" dir=\"ltr\">Conner</td><td class=\"s0\" dir=\"ltr\">Goss</td><td class=\"s0\" dir=\"ltr\">Griffin</td><td class=\"s1\" dir=\"ltr\">8/31/1992</td><td></td><td class=\"s0\" dir=\"ltr\">Topeka</td><td></td><td></td></tr></tbody></table></div></div></div>\n" + "<script type='text/javascript'>\n" + "function posObj(sheet, id, row, col, x, y) {\n" + " var r = document.getElementById(sheet+'R'+row);\n" + " var c = document.getElementById(sheet+'C'+col);\n" + " if (r && c) {\n" + " var s = document.getElementById(id).style;\n" + " var t = y;\n" + " while (r) {\n" + " t += r.offsetTop;\n" + " r = r.offsetParent;\n" + " }\n" + " var l = x;\n" + " while (c) {\n" + " l += c.offsetLeft;\n" + " c = c.offsetParent;\n" + " }\n" + " s.left = l + 'px';\n" + " s.top = t + 'px';\n" + " s.display = 'block';\n" + " s.border = '1px solid #000000';\n" + " }\n" + "};\n" + "function posObjs() {\n" + "};\n" + "posObjs();</script>\n" + "<script type=\"text/javascript\">activeSheetId = '1416730418'; switchToSheet('1416730418');</script></body></html>"; final Pattern pattern = Pattern.compile(regex, Pattern.DOTALL); 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