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

/
/
img

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 = "(?:<TD CLASS=\"label\")(?:.*>)(?s)(?<lbl>.*?)(?:<\\/TD>).*?(?:<TD NOWRAP>).*?(?:type=)\"(?<type>[^\"]*)\".*?(?:name=)\"(?<name>[^\"]*)\".(?:title=)\"(?<title>[^\"]*)\".*?(?:id=)\"(?<id>[^\"]*)\".*?(?:value=)\"(?<value>[^\"]*)\".*?(?:size=)\"(?<size>[^\"]*)\".*?(?:maxlength=)\"(?<maxlength>[^\"]*)\"*.*?<\\/TD>$"; final String string = "<tr>\n" + "<TD CLASS=\"label\" NOWRAP VALIGN=\"MIDDLE\">\n" + "&nbsp;Average_No_of_Direct_Employees:\n" + "&nbsp;\n" + "</TD>\n" + "<TD NOWRAP>\n" + "<INPUT CLASS=\"valueEditable\" TYPE=\"text\" NAME=\"_1_1_10_1\" TITLE=\"Average_No_of_Direct_Employees\" ID=\"_1_1_10_1\" VALUE=\"[LL_FormTag_1_1_10_1 /]\" SIZE=\"20\" MAXLENGTH=\"20\" ONCHANGE=\"markDirty();\">\n" + "</TD>\n" + "</TR>\n\n\n\n" + "<!-- End File: datefield.html (End - _1_1_9_1) -->\n" + "</TD>\n" + "</TR>\n" + "<TR CLASS=\"horizontalCellDivider\" >\n" + "<TD CLASS=\"labelHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/spacer.gif\" WIDTH=\"1\" BORDER=\"0\"></TD>\n" + "<TD CLASS=\"valueHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/tbl-divider-hor.gif\" WIDTH=\"3\" BORDER=\"0\"></TD>\n" + "</TR>\n" + "<TR>\n" + "<TD CLASS=\"label\" NOWRAP VALIGN=\"MIDDLE\">\n" + "&nbsp;Average_No_of_Direct_Employees:\n" + "&nbsp;\n" + "</TD>\n" + "<TD NOWRAP>\n" + "<INPUT CLASS=\"valueEditable\" TYPE=\"text\" NAME=\"_1_1_10_1\" TITLE=\"Average_No_of_Direct_Employees\" ID=\"_1_1_10_1\" VALUE=\"[LL_FormTag_1_1_10_1 /]\" SIZE=\"20\" MAXLENGTH=\"20\" ONCHANGE=\"markDirty();\">\n" + "</TD>\n" + "</TR>\n" + "<TR CLASS=\"horizontalCellDivider\" >\n" + "<TD CLASS=\"labelHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/spacer.gif\" WIDTH=\"1\" BORDER=\"0\"></TD>\n" + "<TD CLASS=\"valueHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/tbl-divider-hor.gif\" WIDTH=\"3\" BORDER=\"0\"></TD>\n" + "</TR>\n" + "<TR>\n" + "<TD CLASS=\"label\" NOWRAP VALIGN=\"MIDDLE\">\n" + "&nbsp;Average_No_of_SubContractors_on-site:\n" + "&nbsp;\n" + "</TD>\n" + "<TD NOWRAP>\n" + "<INPUT CLASS=\"valueEditable\" TYPE=\"text\" NAME=\"_1_1_11_1\" TITLE=\"Average_No_of_SubContractors_on-site\" ID=\"_1_1_11_1\" VALUE=\"[LL_FormTag_1_1_11_1 /]\" SIZE=\"20\" MAXLENGTH=\"20\" ONCHANGE=\"markDirty();\">\n" + "</TD>\n" + "</TR>\n" + "<TR CLASS=\"horizontalCellDivider\" >\n" + "<TD CLASS=\"labelHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/spacer.gif\" WIDTH=\"1\" BORDER=\"0\"></TD>\n" + "<TD CLASS=\"valueHorizontalDivider\" COLSPAN=\"1\"><IMG HEIGHT=\"1\" ALT=\"\" SRC=\"/img/tbl-divider-hor.gif\" WIDTH=\"3\" BORDER=\"0\"></TD>\n" + "</TR>\n" + "<TR>"; final String subst = "<div class=\"medium-6 columns\">\\n <label>${lbl} <!--### INPUT EXAMPLE ### -->\\n <input type=\"${type} <\" NAME=\"${name}\" TITLE=\"${title}\" ID=\"${id}\" VALUE=\"${value}\" SIZE=\"${size}\" MAXLENGTH=\"${maxlength}\" ONCHANGE=\"markDirty();>\\n </label>\\n</div>"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | 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