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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
gm

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 = "^<(?i)(?:input|textarea|\\\\w{0,}TextBox|\\\\w{0,}Field).*(?:name|id)=(?:\\\"|\\')\\w+(?:\\\"|\\').*"; final String string = "{{! my-form.hbs }}\n" + "<form onsubmit={{action \"submit\"}}>\n" + "<label for=\"name\">Name:</label>\n" + "<input type=\"text\" id=\"name\" value={{model.name}}>\n\n" + " <label for=\"email\">Email:</label>\n" + "<input type=\"email\" id=\"email\" value={{model.email}}>\n\n" + " <label for=\"message\">Message:</label>\n" + "<textarea id=\"message\">{{model.message}}</textarea>\n\n" + " <button type=\"submit\">Submit</button>\n" + "</form>\n\n" + "<html>\n" + " <head>\n" + " <title>My Form</title>\n" + " </head>\n" + " <body>\n" + " <form>\n" + " <label for=\"name\">Name:</label>\n" + "<input type=\"text\" name=\"name\" id=\"name\"/>\n" + " <label for=\"email\">Email:</label>\n" + "<input type=\"email\" name=\"email\" id=\"email\"/>\n" + " <label for=\"message\">Message:</label>\n" + "<textarea name=\"message\" id=\"message\"></textarea>\n" + " <button type=\"button\" onclick=\"submitForm()\">Submit</button>\n" + " </form>\n" + " </body>\n" + "</html>"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE); 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