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 = "(?:['\\\"`]([^'\\\"`]*)['\\\"`])"; final String string = "export default {\n" + " root: ({ props, context, parent }) => ({\n" + " class: [\n" + " 'relative',\n\n" + " // Alignments\n" + " 'items-center inline-flex text-center align-bottom justify-center',\n\n" + " // Sizes & Spacing\n" + " 'leading-[normal]',\n" + " {\n" + " 'px-4 py-3': props.size === null,\n" + " 'text-sm py-2 px-3': props.size === 'small',\n" + " 'text-xl py-3 px-4': props.size === 'large'\n" + " },\n" + " {\n" + " 'w-12 p-0 py-3': props.label == null && props.icon !== null\n" + " },\n\n" + " // Shapes\n" + " { 'shadow-lg': props.raised },\n" + " { 'rounded-md': !props.rounded, 'rounded-full': props.rounded },\n" + " { 'rounded-none first:rounded-l-md last:rounded-r-md': parent.instance.$name == 'InputGroup' },\n\n" + " // Link Button\n" + " { 'text-primary-600 bg-transparent border-transparent': props.link },\n\n" + " // Plain Button\n" + " { 'text-white bg-gray-500 border border-gray-500': props.plain && !props.outlined && !props.text },\n" + " // Plain Text Button\n" + " { 'text-surface-500': props.plain && props.text },\n" + " // Plain Outlined Button\n" + " { 'text-surface-500 border border-gray-500': props.plain && props.outlined },\n\n" + " // Text Button\n" + " { 'bg-transparent border-transparent': props.text && !props.plain },\n\n" + " // Outlined Button\n" + " { 'bg-transparent border': props.outlined && !props.plain },\n\n" + " // --- Severity Buttons ---\n\n" + " // Primary Button\n" + " {\n" + " 'text-primary-inverse': !props.link && props.severity === null && !props.text && !props.outlined && !props.plain,\n" + " 'bg-primary': !props.link && props.severity === null && !props.text && !props.outlined && !props.plain,\n" + " 'border border-primary': !props.link && props.severity === null && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Primary Text Button\n" + " { 'text-primary': props.text && props.severity === null && !props.plain },\n" + " // Primary Outlined Button\n" + " { 'text-primary border border-primary': props.outlined && props.severity === null && !props.plain },\n\n" + " // Secondary Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'secondary' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-surface-500 dark:bg-surface-400': props.severity === 'secondary' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-surface-500 dark:border-surface-400': props.severity === 'secondary' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Secondary Text Button\n" + " { 'text-surface-500 dark:text-surface-300': props.text && props.severity === 'secondary' && !props.plain },\n" + " // Secondary Outlined Button\n" + " { 'text-surface-500 dark:text-surface-300 border border-surface-500 hover:bg-surface-300/20': props.outlined && props.severity === 'secondary' && !props.plain },\n\n" + " // Success Button\n" + " {\n" + " 'text-white dark:text-green-900': props.severity === 'success' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-green-500 dark:bg-green-400': props.severity === 'success' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-green-500 dark:border-green-400': props.severity === 'success' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Success Text Button\n" + " { 'text-green-500 dark:text-green-400': props.text && props.severity === 'success' && !props.plain },\n" + " // Success Outlined Button\n" + " { 'text-green-500 border border-green-500 hover:bg-green-300/20': props.outlined && props.severity === 'success' && !props.plain },\n\n" + " // Info Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'info' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-blue-500 dark:bg-blue-400': props.severity === 'info' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-blue-500 dark:border-blue-400': props.severity === 'info' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Info Text Button\n" + " { 'text-blue-500 dark:text-blue-400': props.text && props.severity === 'info' && !props.plain },\n" + " // Info Outlined Button\n" + " { 'text-blue-500 border border-blue-500 hover:bg-blue-300/20 ': props.outlined && props.severity === 'info' && !props.plain },\n\n" + " // Warning Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'warning' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-orange-500 dark:bg-orange-400': props.severity === 'warning' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-orange-500 dark:border-orange-400': props.severity === 'warning' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Warning Text Button\n" + " { 'text-orange-500 dark:text-orange-400': props.text && props.severity === 'warning' && !props.plain },\n" + " // Warning Outlined Button\n" + " { 'text-orange-500 border border-orange-500 hover:bg-orange-300/20': props.outlined && props.severity === 'warning' && !props.plain },\n\n" + " // Help Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'help' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-purple-500 dark:bg-purple-400': props.severity === 'help' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-purple-500 dark:border-purple-400': props.severity === 'help' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Help Text Button\n" + " { 'text-purple-500 dark:text-purple-400': props.text && props.severity === 'help' && !props.plain },\n" + " // Help Outlined Button\n" + " { 'text-purple-500 border border-purple-500 hover:bg-purple-300/20': props.outlined && props.severity === 'help' && !props.plain },\n\n" + " // Danger Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'danger' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-red-500 dark:bg-red-400': props.severity === 'danger' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-red-500 dark:border-red-400': props.severity === 'danger' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Danger Text Button\n" + " { 'text-red-500 dark:text-red-400': props.text && props.severity === 'danger' && !props.plain },\n" + " // Danger Outlined Button\n" + " { 'text-red-500 border border-red-500 hover:bg-red-300/20': props.outlined && props.severity === 'danger' && !props.plain },\n" + " // Contrast Button\n" + " {\n" + " 'text-white dark:text-surface-900': props.severity === 'contrast' && !props.text && !props.outlined && !props.plain,\n" + " 'bg-surface-900 dark:bg-surface-0': props.severity === 'contrast' && !props.text && !props.outlined && !props.plain,\n" + " 'border border-surface-900 dark:border-surface-0': props.severity === 'contrast' && !props.text && !props.outlined && !props.plain\n" + " },\n" + " // Contrast Text Button\n" + " { 'text-surface-900 dark:text-surface-0': props.text && props.severity === 'contrast' && !props.plain },\n" + " // Contrast Outlined Button\n" + " { 'text-surface-900 dark:text-surface-0 border border-surface-900 dark:border-surface-0': props.outlined && props.severity === 'contrast' && !props.plain },\n\n" + " // --- Severity Button States ---\n" + " 'focus:outline-none focus:outline-offset-0 focus:ring',\n\n" + " // Link\n" + " { 'focus:ring-primary': props.link },\n\n" + " // Plain\n" + " { 'hover:bg-gray-600 hover:border-gray-600': props.plain && !props.outlined && !props.text },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-surface-300/20': props.plain && (props.text || props.outlined) },\n\n" + " // Primary\n" + " { 'hover:bg-primary-hover hover:border-primary-hover': !props.link && props.severity === null && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-primary': props.severity === null },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-primary-300/20': (props.text || props.outlined) && props.severity === null && !props.plain },\n\n" + " // Secondary\n" + " { 'hover:bg-surface-600 dark:hover:bg-surface-300 hover:border-surface-600 dark:hover:border-surface-300': props.severity === 'secondary' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-surface-400/50 dark:focus:ring-surface-300/50': props.severity === 'secondary' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-surface-300/20': (props.text || props.outlined) && props.severity === 'secondary' && !props.plain },\n\n" + " // Success\n" + " { 'hover:bg-green-600 dark:hover:bg-green-300 hover:border-green-600 dark:hover:border-green-300': props.severity === 'success' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-green-400/50 dark:focus:ring-green-300/50': props.severity === 'success' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-green-300/20': (props.text || props.outlined) && props.severity === 'success' && !props.plain },\n\n" + " // Info\n" + " { 'hover:bg-blue-600 dark:hover:bg-blue-300 hover:border-blue-600 dark:hover:border-blue-300': props.severity === 'info' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-blue-400/50 dark:focus:ring-blue-300/50': props.severity === 'info' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-blue-300/20': (props.text || props.outlined) && props.severity === 'info' && !props.plain },\n\n" + " // Warning\n" + " { 'focus:ring-orange-400/50 dark:focus:ring-orange-300/50': props.severity === 'warning' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-orange-600 ': props.severity === 'warning' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-orange-600 ': props.severity === 'warning' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-orange-300/20': (props.text || props.outlined) && props.severity === 'warning' && !props.plain },\n\n" + " // Help\n" + " { 'hover:bg-purple-600 dark:hover:bg-purple-300 hover:border-purple-600 dark:hover:border-purple-300': props.severity === 'help' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-purple-400/50 dark:focus:ring-purple-300/50': props.severity === 'help' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-purple-300/20': (props.text || props.outlined) && props.severity === 'help' && !props.plain },\n\n" + " // Danger\n" + " { 'hover:bg-red-600 dark:hover:bg-red-300 hover:border-red-600 dark:hover:border-red-300': props.severity === 'danger' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-red-400/50 dark:focus:ring-red-300/50': props.severity === 'danger' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-red-300/20': (props.text || props.outlined) && props.severity === 'danger' && !props.plain },\n" + " // Contrast\n" + " { 'hover:bg-surface-800 dark:hover:bg-surface-100 hover:border-surface-800 dark:hover:border-surface-100': props.severity === 'contrast' && !props.text && !props.outlined && !props.plain },\n" + " { 'focus:ring-surface-500 dark:focus:ring-surface-400': props.severity === 'contrast' },\n" + " // Text & Outlined Button\n" + " { 'hover:bg-surface-900/10 dark:hover:bg-[rgba(255,255,255,0.03)]': (props.text || props.outlined) && props.severity === 'contrast' && !props.plain },\n" + " // Disabled\n" + " { 'opacity-60 pointer-events-none cursor-default': context.disabled },\n\n" + " // Transitions\n" + " 'transition duration-200 ease-in-out',\n\n" + " // Misc\n" + " 'cursor-pointer overflow-hidden select-none'\n" + " ]\n" + " }),\n" + " label: ({ props }) => ({\n" + " class: [\n" + " 'duration-200 p-4 mt-4 mb-9 ring-1 ',\n" + " 'font-bold',\n" + " {\n" + " 'hover:underline': props.link\n" + " },\n" + " { 'flex-1': props.label !== null, 'invisible w-0': props.label == null }\n" + " ]\n" + " }),\n" + " icon: ({ props }) => ({\n" + " class: [\n" + " 'mx-0',\n" + " {\n" + " 'mr-2': props.iconPos == 'left' && props.label != null,\n" + " 'ml-2 order-1': props.iconPos == 'right' && props.label != null,\n" + " 'mb-2': props.iconPos == 'top' && props.label != null,\n" + " 'mt-2': props.iconPos == 'bottom' && props.label != null\n" + " }\n" + " ]\n" + " }),\n" + " loadingicon: ({ props }) => ({\n" + " class: [\n" + " 'h-4 w-4',\n" + " 'mx-0',\n" + " {\n" + " 'ml-2 order-1': props.iconPos == 'right' && props.label != null,\n" + " 'mb-2': props.iconPos == 'top' && props.label != null,\n" + " 'mt-2': props.iconPos == 'bottom' && props.label != null\n" + " },\n" + " 'animate-spin'\n" + " ]\n" + " }),\n" + " badge: ({ props }) => ({\n" + " class: [ { 'ml-2 w-4 h-4 leading-none flex items-center justify-center': props.badge } ]\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