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 = "(?:doFilter\\s*[:=]\\s*function|function\\s*doFilter)\\([^)]*\\)\\s*\\{((?:[^\\{\\}]+|\\{[^\\}]+\\})*)\\}"; final String string = "doFilter : function(){\n" + " var filters = $$('#'+this.containerId+' .filter input', '#'+this.containerId+' .filter select');\n" + " var elements = [];\n" + " for(var i in filters){\n" + " if(filters[i].value && filters[i].value.length) elements.push(filters[i]);\n" + " }\n" + " if (!this.doFilterCallback || (this.doFilterCallback && this.doFilterCallback())) {\n" + " this.reload(this.addVarToUrl(this.filterVar, encode_base64(Form.serializeElements(elements))));\n" + " }\n" + " },\n" + "resetFilter = function(){\n" + " this.reload(this.addVarToUrl(this.filterVar, ''));\n" + "},\n" + "checkCheckboxes : function(element){\n" + " elements = Element.select($(this.containerId), 'input[name=\"'+element.name+'\"]');\n" + " for(var i=0; i<elements.length;i++){\n" + " this.setCheckboxChecked(elements[i], element.checked);\n" + " }\n" + "},\n" + "function doFilter(grid, event){\n" + " var element = Event.findElement(event, 'tr');\n" + " if(['a', 'input', 'select', 'option'].indexOf(Event.element(event).tagName.toLowerCase())!=-1) {\n" + " return;\n" + " }\n\n" + " if(element.title){\n" + " setLocation(element.title);\n" + " }\n" + "},\n" + "function openGridRow(grid, event){\n" + " var element = Event.findElement(event, 'tr');\n" + " if(['a', 'input', 'select', 'option'].indexOf(Event.element(event).tagName.toLowerCase())!=-1) {\n" + " return;\n" + " }\n\n" + " if(element.title){\n" + " setLocation(element.title);\n" + " }\n" + "}\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