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 = "getObj\\(\"Frm_Logintoken\"\\).value = \"(.*)\";"; final String string = "\n" + "<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\"\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\"><html xmlns=\"http://www.w3.org/1999/xhtml\">\n" + "<head>\n" + "<META HTTP-EQUIV=\"pragma\" CONTENT=\"no-cache\">\n" + "<META HTTP-EQUIV=\"Cache-Control\" CONTENT=\"no-cache, must-revalidate\">\n" + "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=iso-8859-1\" />\n" + "<title>&#90;&#88;&#72;&#78;&#32;&#72;&#49;&#48;&#56;&#78;&#32;&#86;&#50;&#46;&#53;</title>\n" + "<LINK REL=\"stylesheet\" HREF=\"css/login.css\" TYPE=\"text/css\" />\n" + "<LINK REL=\"stylesheet\" HREF=\"css/styleen.css\" TYPE=\"text/css\" />\n" + "<script>\n\n" + "function getObj(id)\n" + "{\n" + "return(document.getElementById(id));\n" + "}\n" + "var SetTFlag = 0;\n" + "var maxtime;\n" + "var interval;\n" + "function setTime()\n" + "{\n" + "if(window.name>=60 || window.name<0 || window.name==\"\")\n" + "{\n" + "maxtime = Math.min(60, 0 + 60 - 218143);\n" + "}\n" + "else\n" + "{\n" + "maxtime = window.name;\n" + "}\n" + "if(maxtime>=0)\n" + "{\n" + "seconds = maxtime;\n" + "getObj(\"time\").innerHTML=seconds+\" secs\";\n" + "if (maxtime == 0)\n" + "{\n" + "setDisable();\n" + "SetTFlag =0;\n" + "window.name=\"\";\n" + "if(interval)\n" + "{\n" + "clearInterval(interval);\n" + "interval = 0;\n" + "}\n" + "}\n" + "else\n" + "{\n" + "--maxtime;\n" + "SetTFlag = 1;\n" + "window.name = maxtime;\n" + "}\n" + "}\n" + "}\n" + "function setinner(type)\n" + "{\n" + "if (SetTFlag ==0)\n" + "{\n" + "getObj(\"myLayer\").style.visibility = type ;\n" + "}\n" + "}\n" + "function Transfer_meaning(id,value)\n" + "{\n" + "getObj(id).value=value;\n" + "}\n" + "function ChangeLang()\n" + "{\n" + "var lang = \"English\";\n" + "getObj(\"_lang\").disabled = false;\n" + "getObj(\"Frm_Username\").disabled = true;\n" + "getObj(\"Frm_Password\").disabled = true;\n" + "if(true != getObj(\"TestLang01\").disabled)\n" + "{\n" + "if (\"English\" == lang)\n" + "{\n" + "getObj(\"_lang\").value = \"Chinese\";\n" + "}\n" + "else if (\"Chinese\" == lang)\n" + "{\n" + "getObj(\"_lang\").value = \"English\";\n" + "}\n" + "getObj(\"action\").value = \"setlang\";\n" + "getObj(\"Frm_Username\").disabled = true;\n" + "getObj(\"Frm_Password\").disabled = true;\n" + "getObj(\"LoginId\").disabled = true;\n" + "document.fLogin.submit();\n" + "}\n" + "}\n" + "</script>\n" + "</head>\n\n" + "<body>\n" + "<div id=\"container\">\n" + "<div id=\"myLayer\" onmousedown=\"setinner('hidden')\" style=\"position:absolute; width:185px; height:91px; z-index:9; right: 50px; top: 140px; background: url(img/pop_up.gif) no-repeat; border: 1px none #000000; visibility: hidden;\">\n" + "<div id=\"Layer1\" style=\"position:absolute; width:180px; height:45px; z-index:10; left: 2px; top: 28px;\">\n" + "<table width=\"183\" border=\"0\">\n" + "<tr>\n" + "<td width=\"183\">&nbsp;&nbsp;<font id=\"errmsg\" class=\"notecontent\" ></font><span id=\"time\" style=\"color:red;display:none;\"></span></td>\n" + "</tr>\n" + "</table>\n" + "</div>\n" + "<div id=\"Layer3\" style=\"position:absolute; width:140px; height:10px; z-index:11; left: 34px; top: 9px; font-size: 8pt;\">\n" + "<font class=\"note\" id=\"errnote\">&nbsp;Error</font>\n" + "</div>\n" + "</div>\n" + "<!--head²¿·Ö¿ªÊ¼-->\n" + "<div id=\"head\">\n" + "<div class=\"type\"><font id=\"\">&#90;&#88;&#72;&#78;&#32;&#72;&#49;&#48;&#56;&#78;&#32;&#86;&#50;&#46;&#53;</font></div>\n" + "<div id=\"banner\" style=\"background-image:url(img/banner.gif); background-repeat:no-repeat\"></div>\n" + "</div>\n" + "<!--head²¿·Ö½áÊø-->\n" + "<!--content²¿·Ö¿ªÊ¼-->\n" + "<div id=\"loginArea\">\n" + "<form name=\"fLogin\" id=\"fLogin\" method=\"post\" onsubmit=\"return false;\" action=\"\">\n" + "<input type=\"hidden\" name=\"_lang\" id=\"_lang\" value=\"\" disabled>\n" + "<input type=\"hidden\" name=\"frashnum\" id=\"frashnum\" value=\"\">\n" + "<input type=\"hidden\" name=\"action\" id=\"action\" value=\"login\">\n" + "<input type=\"hidden\" name=\"Frm_Logintoken\" id=\"Frm_Logintoken\" value=\"\">\n" + "<!--ÄÚÈÝ¿ªÊ¼-->\n" + "<div class=\"login_frame\">\n" + "<ul class=\"login_title\">\n" + "<li class=\"login_title_left\"></li>\n" + "<li class=\"login_title_center\">Please login to continue...</li>\n\n" + "<li class=\"login_title_right\"></li>\n" + "</ul>\n" + "<div class=\"content login_content\">\n" + "<ul class=\"login_blank\"></ul>\n" + "<ul class=\"login_ul_1\">\n" + "<li class=\"login_li_1\"><span>Username</span></li>\n" + "<li class=\"login_li_2\">\n" + "<input type=\"text\" class=\"username\" name=\"Username\" id=\"Frm_Username\">\n" + "</li>\n" + "</ul>\n" + "<ul class=\"login_blank\"></ul>\n" + "<ul class=\"login_ul_1\">\n" + "<li class=\"login_li_1\"><span>Password</span></li>\n" + "<li class=\"login_li_2\">\n" + "<input type=\"password\" class=\"password\" name=\"Password\" id=\"Frm_Password\">\n" + "</li>\n" + "<li class=\"login_li_3\">\n" + "<input class=\"login\" type=\"submit\" id=\"LoginId\" value=\"Login\" onclick=\"dosubmit()\">\n" + "</li>\n" + "</ul>\n" + "</div>\n" + "</div>\n" + "<!--ÄÚÈݽáÊø-->\n" + "</form>\n" + "</div>\n" + "<!--bottom²¿·Ö¿ªÊ¼-->\n\n" + "<div style=\"font-family: Arial;font-size: 12px;text-align:center;\"> &copy; 2008-2015 ZTE Corporation. All rights reserved </div>\n\n" + "<div class=\"bottom_line\"></div>\n" + "<div id=\"bottomx\"></div>\n" + "<!--bottom²¿·Ö½áÊø-->\n" + "</div>\n" + "</body>\n" + "</html>\n" + "<script>\n\n" + "window.name=\"\";\n\n" + "function SetDisabled()\n" + "{\n" + "getObj(\"errmsg\").innerHTML = \"You have input the wrong username or password for three times. Please try again a minute later.\";\n" + "getObj(\"Frm_Username\").disabled = true;\n" + "getObj(\"Frm_Password\").disabled = true;\n" + "getObj(\"LoginId\").disabled = true;\n\n" + "getObj(\"myLayer\").style.visibility = \"visible\" ;\n" + "getObj(\"time\").style.display = \"\" ;\n" + "interval = setInterval(\"setTime()\",1000);\n" + "}\n" + "function setDisable()\n" + "{\n" + "if (SetTFlag == 1)\n" + "{\n" + "getObj(\"Frm_Username\").disabled = false;\n" + "getObj(\"Frm_Password\").disabled = false;\n" + "getObj(\"LoginId\").disabled = false;\n\n" + "getObj(\"time\").style.display = \"none\";\n" + "getObj(\"myLayer\").style.visibility = \"hidden\";\n" + "}\n" + "}\n" + "function dosubmit()\n" + "{\n" + "if (getObj(\"Frm_Username\").value == \"\")\n" + "{\n" + "getObj(\"errmsg\").innerHTML = \"Username cannot be empty.\";\n" + "getObj(\"myLayer\").style.visibility = \"visible\" ;\n" + "return;\n" + "}\n" + "else\n" + "{\n" + "getObj(\"LoginId\").disabled = true;\n" + "getObj(\"Frm_Logintoken\").value = \"7\";\n" + "document.fLogin.submit();\n" + "}\n" + "}\n" + "</script>\n"; 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