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 = "\"type\":\"(?P<threat_purpose>[^:]+):(?P<threat_resource_affected>[^\\/]+)\\/(?P<threat_name>[^!]+)\\!(?P<threat_artifact>[^\"]*?)"; final String string = "{\"detail-type\":\"GuardDuty Finding\",\"resources\":[],\"source\":\"aws.guardduty\",\"id\":\"xxxxx-xx\",\"detail\":{\"schemaVersion\":\"2.0\",\"accountId\":\"1234567890\",\"region\":\"us-west-2\",\"partition\":\"aws\",\"id\":\"xxxxxxxx\",\"arn\":\"arn:aws:guardduty:us-west-2:1234567890:detector/XXXXXXX/finding/xxxxxxx\",\"type\":\"Trojan:EC2/PhishingDomainRequest!DNS\",\"resource\":{\"resourceType\":\"Instance\",\"instanceDetails\":{\"instanceId\":\"i-99999999\",\"instanceType\":\"m3.xlarge\",\"launchTime\":\"2016-08-02T02:05:06Z\",\"productCodes\":[{\"productCodeId\":\"GeneratedFindingProductCodeId\",\"productCodeType\":\"GeneratedFindingProductCodeType\"}],\"iamInstanceProfile\":{\"arn\":\"GeneratedFindingInstanceProfileArn\",\"id\":\"GeneratedFindingInstanceProfileId\"},\"networkInterfaces\":[{\"ipv6Addresses\":[],\"privateDnsName\":\"GeneratedFindingPrivateDnsName\",\"privateIpAddress\":\"127.0.0.1\",\"privateIpAddresses\":[{\"privateDnsName\":\"GeneratedFindingPrivateName\",\"privateIpAddress\":\"127.0.0.1\"}],\"subnetId\":\"GeneratedFindingSubnetId\",\"vpcId\":\"ein-ffdd1234\",\"securityGroups\":[{\"groupName\":\"SecurityGroup01\",\"groupId\":\"GeneratedFindingSecurityId\"}],\"publicDnsName\":\"bbb.com\",\"publicIp\":\"127.0.0.1\"}],\"tags\":[{\"key\":\"GeneratedFindingInstaceTag1\",\"value\":\"GeneratedFindingInstaceValue1\"},{\"key\":\"ami-99999999\",\"imageDescription\":\"GeneratedFindingInstaceImageDescription\"}],\"service\":{\"serviceName\":\"guardduty\",\"detectorId\":\"xxxxxx\",\"action\":{\"actionType\":\"DNS_REQUEST\",\"dnsRequestAction\":{\"domain\":\"GeneratedFindingDomainName\",\"protocol\":\"UDP\",\"blocked\":true}},\"resourceRole\":\"TARGET\",\"additionalInfo\":{\"threatListName\":\"GeneratedFindingThreatListName\",\"sample\":true},\"eventFirstSeen\":\"2020-06-02T20:22:26.350Z\",\"eventLastSeen\":\"2020-06-03T20:22:26.350Z\",\"archived\":false,\"count\":1},\"severity\":8,\"createdAt\":\"2020-06-02T20:22:26.350Z\",\"updatedAt\":\"2020-06-03T20:22:26.350Z\",\"title\":\"Trojan:EC2/PhishingDomainRequest!DNS\",\"description\":\"Trojan:EC2/PhishingDomainRequest!DNS\"}}},\"time\":\"2018-02-28T20:25:00Z\",\"region\":\"us-west-2\",\"version\":\"0\",\"account\":\"1234567890\"}"; 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