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
Processing...

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 = "^(?=(.{0,1500}language[^\\n]*\\n[^\\n]*\\n[^\\n]*))(?=(.{0,1500}experience[^\\n]*\\n[^\\n]*\\n[^\\n]*))(?=(.{0,1500}acquire[^\\n]*\\n[^\\n]*\\n[^\\n]*))"; final String string = "materials the in the case of language\n" + "what was taken further than assumed sort\n" + "of again though experiments but seems\n" + "obvious is that the basic elements\n" + "of language say concepts or words if\n" + "there's any difference between them\n" + "those must be primarily generated\n" + "internally their complexity and richness\n" + "is such that they can't possibly be\n" + "acquired from experience they were what\n" + "were called the common notions or innate\n" + "ideas formed by some internal generative\n" + "process that's structured in some\n" + "fashion this and there was a good but\n" + "about how this is done suggesting that\n" + "what's involved is you start with but\n" + "are now called gustave properties\n" + "notions of casual relation notions of\n" + "agency anthropomorphic perspectives all\n" + "familiar with the way we perceive and\n" + "think about the natural world\n" + "so you see you you talk about a comet as\n" + "aiming towards the Earth and fortunately\n"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.DOTALL); 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