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

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 = "(compile|testCompile|implementation|testImplementation|compileOnly|runtime|testRuntime|[a-zA-Z0-9_]{1,100})\\sgroup\\:\\s['\"](.*)['\"],\\sname\\:\\s['\"](.*)['\"],\\sversion\\:\\s['\"](.*)['\"]|(compile|testCompile|implementation|testImplementation|compileOnly|runtime|testRuntime|[a-zA-Z0-9_]{1,100})\\s['\"](.*):(.*):(.*)['\"]|(compile|testCompile|implementation|testImplementation|compileOnly|runtime|testRuntime|[a-zA-Z0-9_]{1,100})\\(['\"](.*):(.*):(.*)['\"]\\)"; final String string = "compile group: 'commons-net', name: 'commons-net', version: '3.1.2'\n" + "testCompile group: 'org.spockframework', name: 'spock-core', version: '2.0-M1-groovy-3.0'\n" + "implementation group: 'commons-net', name: 'commons-net', version: '3.7.2'\n" + "testImplementation group: 'org.spockframework', name: 'spock-core', version: '2.0-M4-groovy-3.0'\n" + "implementation \"org.apache.httpcomponents:httpclient:latest.release\"\n" + "implementation 'org.apache.httpcomponents:httpclient:1.0.0'\n" + "compile \"com.h2database:h2:1.4.197\"\n" + "compile(\"com.github.bkenn:kfoenix:0.1.2-SNAPSHOT\")\n" + "compile group: \"com.jfoenix\", name: \"jfoenix\", version: \"8.0.7\"\n" + "compile \"org.jooq:jooq:3.11.5\"\n" + "jooqRuntime('com.h2database:h2:1.4.197')\n" + "jooqRuntime(\"com.h2database:h2:1.4.197\")\n" + "jooqRuntime 'com.h2database:h2:1.4.197'\n" + "jooqRuntime \"com.h2database:h2:1.4.197\""; 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