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

r"
"
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 = "^arn:(aws|aws-cn|aws-us-gov):([a-zA-Z0-9-]+):([a-zA-Z0-9-]*):(\\d{12}|):([^:/]+)([:/].*)?$"; final String string = "AWS\n" + "arn:aws:s3:::my-s3-bucket\n" + "arn:aws:iam::123456789012:user/JohnDoe\n" + "arn:aws:dynamodb:us-east-1:123456789012:table/UserTable\n" + "arn:aws:lambda:us-west-2:123456789012:function:ProcessData\n" + "arn:aws:ec2:us-east-1:123456789012:instance/i-0abcd1234efgh5678\n\n" + "GOOGLE CLOUD\n" + "projects/my-project-id/buckets/my-storage-bucket\n" + "projects/my-project-id/zones/us-central1-a/instances/instance-1\n" + "projects/my-project-id/topics/my-pubsub-topic\n" + "projects/my-project-id/datasets/my_bigquery_dataset\n" + "projects/my-project-id/instances/my-cloud-sql-instance\n\n" + "AZURE\n" + "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/MyResourceGroup/providers/Microsoft.KeyVault/vaults/MyKeyVault\n" + "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/MyResourceGroup/providers/Microsoft.Storage/storageAccounts/mystorageacct\n" + "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/MyResourceGroup/providers/Microsoft.Compute/virtualMachines/MyVM\n" + "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/MyResourceGroup/providers/Microsoft.Web/sites/MyAppService\n" + "/subscriptions/12345678-1234-1234-1234-123456789012/resourceGroups/MyResourceGroup/providers/Microsoft.DocumentDB/databaseAccounts/MyCosmosDB"; 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