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

/
/
gmi

Test String

Code Generator

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 id=\"(.*?)<\\/a>"; final String string = "{% comment %} \n" + "Use this template to create the Appian_Release_Notes.md page for each new version of Appian. Any changes to this template should be discussed with the Information Development team. \n" + "{% endcomment %}\n\n" + "New features are described below in detail. Behavior changes, resolved issues, deprecations, and removals are called out their own sections.\n\n" + "{% comment %} \n" + "### <a id=\"Example_New_Feature\"></a> Example New Feature ###\n\n" + "This is a short description of the new feature. Group two or more closely related features using a common section with h4 subsections. Link to associated documentation as shown below (based on the number of links).\n\n" + "See also: [Associated Documentation](Associated_Documentation.md)\n\n" + "See also: [Associated Documentation](Associated_Documentation.md) and [Associated Documentation](Associated_Documentation.md)\n\n" + "See also: [Associated Documentation](Associated_Documentation.md), [Associated Documentation](Associated_Documentation.md), and [Associated Documentation](Associated_Documentation.md)\n" + "{% endcomment %}\n\n\n" + "## <a id=\"User_Interfaces\"></a> User Interfaces ##\n\n" + "This section describes new features for user interfaces, including Tempo, sites, and embedded interfaces.\n\n" + "### Sites Revolution ###\n\n" + "#### <a id=\"Tempo_Reports_in_Sites\"></a> Tempo Reports in Sites ###\n\n" + "In addition to task reports, actions and record types, designers can now configure sites to have Tempo reports. Making it easier for sites only users to view and analyze data.\n\n" + "<img class=\"screenshot\" src=\"images/release_notes/SitesTempoReports.png\"/>\n\n" + "[configure sites with reports](Sites.md#Configure_a_Site_Page).\n\n" + "#### <a id=\"Inline_Task_Management\"></a> Inline Task Management ###\n\n" + "Task management has improved for users of all Appian user environments. All task management controls for SAIL [tasks](Tasks.md), including save changes, reassign, and reject, have been moved to above the task form.\n\n" + "The left-hand navigation bar no longer appears in Tempo when viewing SAIL tasks, allowing task forms to occupy the full page width.\n\n" + "These task management controls are now available to [sites](Sites.md) users for the first time.\n\n" + "Users of [embedded](Embedded_Interfaces.md) tasks now have the option to save changes to SAIL tasks.\n\n" + "<img src=\"images/release_notes/InlineTaskControls.png\" class=\"screenshot\"/>\n\n\n" + "#### <a id=\"User_Record_in_Sites\"></a> User Record in Sites ###\n\n" + "We have made it possible for designers to configure the User record and User record links in sites.\n\n" + "<img class=\"screenshot\" src=\"images/release_notes/SitesUserRecord.png\"/>\n\n" + "#### <a id=\"User_Profile_in_Sites\"></a> User Profile in Sites ###\n\n" + "Users can now update their profiles in a site by clicking on their avatar in the header and clicking on the Profile button. \n\n" + "<img class=\"screenshot\" src=\"images/release_notes/SitesUserProfile.png\"/>\n\n" + "#### Wider Sites ###\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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