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

/
/
gm

Test String

Substitution

Processing...

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 = "(.+ Muffin)"; final String string = "Raspberry Muffin\n" + "Raspberry \n" + "Raisin Muffin\n" + "Muffin\n" + "Wings\n" + "Soup\n" + "Toast\n" + "Tater Tots\n" + "Tatted Tots\n" + "Tatter Tots\n" + "Shake\n" + "Salami\n" + "Salmon\n" + "Hash Browns\n" + "Quinoa\n" + "Raspberry Muffin\n" + "Bud Light\n" + "Coke Zero\n" + "Diet Coke\n" + "French Onion Soup\n" + "Tacos\n" + "Turkey\n" + "What time is it\n" + "Cranberries\n" + "Yogurt\n" + "YT\n" + "Peas\n" + "Chocolate\n" + "Pancakes\n" + "Lime\n" + "Hot Dog\n" + "French Fried\n" + "Egg\n" + "Sashimi\n" + "Cherrios\n" + "Buzzy\n" + "Carrot \n" + "Coke\n" + "Granola\n" + "Hi \n" + "Gum\n" + "test\n" + "Hamburger\n" + "Lol\n" + "Meat\n" + "foot\n" + "Omelet\n" + "Pretzels\n" + "Siracha hot sauce\n" + "Strawberry smoothie\n" + "What now?\n" + "Cheerios\n" + "pretzel\n" + "Doctor Pepper\n" + "Root Beer\n" + "diet root beer\n" + "Orange\n" + "Canola\n" + "Plum\n" + "Spaghetti\n" + "Sushi\n" + "Agave\n" + "Agave syrup\n" + "Alcohol\n" + "Almond\n" + "Almonds\n" + "Apple\n" + "Apples\n" + "Apples\n" + "Artichoke\n" + "Asparagus\n" + "Are these okay?\n" + "Are these ok?\n" + "Avocado\n" + "Avocado oil\n" + "badlist\n" + "Bacon\n" + "Bananas\n" + "Beans\n" + "Beans / Legumes\n" + "Beef\n" + "Beet sugar\n" + "Beets\n" + "Blackberries\n" + "Blueberries\n" + "Brazil nuts\n" + "bread\n" + "Broccoli\n" + "Brussels sprouts\n" + "Butter\n" + "Cabbage\n" + "Candied nuts\n" + "Can\n" + "candy\n" + "Canola oil\n" + "Carrots\n" + "Cashew\n" + "Cashews\n" + "Cashews\n" + "Cauliflower\n" + "Celery\n" + "Celery root\n" + "cereal\n" + "Cheese\n" + "Cheetos\n" + "Cherries\n" + "Chia and Flax seeds\n" + "Chicken\n" + "Chickpeas\n" + "coconut sugar\n" + "Coffee\n" + "Corn\n" + "Corn oil\n" + "Crab\n" + "Cream\n" + "Cream cheese\n" + "Cucumber\n" + "Diet coke\n" + "diet soda\n" + "Eggplant\n" + "Eggs\n" + "Fish\n" + "French fries\n" + "Fried chicken\n" + "Frozen yogurt\n" + "Fruit\n" + "Ghee\n" + "Gin\n" + "grains\n" + "Green onions\n" + "Green peas\n" + "Greens (spinach, kale, etc.)\n" + "Guacamole\n" + "Herbs (parsley, basil, etc.)\n" + "Honeyed nuts\n" + "Ice cream\n" + "Jerky\n" + "kale\n" + "ketchup\n" + "Lamb\n" + "Lard\n" + "Lettuce\n" + "Lima beans\n" + "Lobster\n" + "Macadamias\n" + "Mango\n" + "Mayo\n" + "Mayonnaise\n" + "Meatballs\n" + "Meatloaf\n" + "meatloaf\n" + "Melon\n" + "Milk\n" + "Milky Way\n" + "Mushrooms\n" + "Mussels\n" + "Nuts\n" + "Olive oil\n" + "Olives\n" + "Onions\n" + "Oranges\n" + "Oysters\n" + "Palm sugar\n" + "Parsnips\n" + "pasta\n" + "Peach\n" + "Pears\n" + "Pecans\n" + "Peppers\n" + "pizza\n" + "Plantains\n" + "Plums\n" + "Popcorn\n" + "Popsicle\n" + "Pork\n" + "potato\n" + "Potatoes\n" + "poultry\n" + "Pumpkin\n" + "Raspberries\n" + "Rice\n" + "Rum\n" + "Shrimp\n" + "Snack mix\n" + "Soda\n" + "Soybean oil\n" + "Steak\n" + "Stevia\n" + "Strawberries\n" + "Sugar\n" + "Sugar-free soda\n" + "Sugared nuts\n" + "Sunflower seeds\n" + "Sweet potatoes and yams\n" + "Tallow\n" + "Tea\n" + "Tomatoes\n" + "tomatoes\n" + "Trail mix\n" + "Vegetable oil\n" + "Vodka\n" + "Walnuts\n" + "Water\n" + "What can I say\n" + "Whiskey\n" + "whole grain bread\n" + "Whole Milk\n" + "why\n" + "wine\n" + "Winter squash\n" + "Xylitol\n" + "Yogurt-covered nuts\n" + "Zucchini\n" + "zzz"; final String subst = "$1"; final Pattern pattern = Pattern.compile(regex, 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