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 = "^(?:time=\\\"(?<longtime>\\d{4}-\\d{2}-\\d{2}\\D{1}\\d{2}:\\d{2}:\\d{2}\\+\\d{2}:\\d{2})\\\") (?:level=(?<level>(info|warn|error))) (?:msg=\\\"(?<msg>.*)\\\") (((?:duration=(?<duration>\\d{1,9}.\\d{1,9})) (?:gitaly_embedded=(?<gitaly_embedded>[^ ]+)) (?:method=(?<method>(POST|GET))))|((?:body=\"(?<body>.*)\") (?<code>code=\\d{3}) (?:method=(?<method2>(POST|GET)))|(?<command>command=\".*\"))|(?:key_id=key-(?<key_id>)\\d{3})) (?:pid=(?<pid>\\d{1,5})) (?:url=\\\"(((?<url>.*)\\\"))|(?:user=\"(?<user>.*)\")|(?:public_key=\"(?<public_key>.*)\"))"; final String string = "time=\"2019-06-10T09:23:34+03:00\" level=info msg=\"finished HTTP request\" duration=0.02119909 gitaly_embedded=false method=POST pid=45053 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:34+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"internet_platform/auto_tests.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-548\\\",\\\"gl_project_path\\\":\\\"internet_platform/auto_tests\\\"},\\\"gl_repository\\\":\\\"project-548\\\",\\\"gl_project_path\\\":\\\"internet_platform/auto_tests\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45053 user=\"user with id key-147\"\n" + "time=\"2019-06-10T09:23:38+03:00\" level=info msg=\"finished HTTP request\" duration=0.021129036 gitaly_embedded=false method=POST pid=45077 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:38+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"erl-omsk/eps-storage-web.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-1375\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-storage-web\\\"},\\\"gl_repository\\\":\\\"project-1375\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-storage-web\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45077 user=\"user with id key-147\"\n" + "time=\"2019-06-10T09:23:42+03:00\" level=info msg=\"finished HTTP request\" duration=0.021581528 gitaly_embedded=false method=POST pid=45169 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:42+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"erl-omsk/smev-fssp.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-63\\\",\\\"gl_project_path\\\":\\\"erl-omsk/smev-fssp\\\"},\\\"gl_repository\\\":\\\"project-63\\\",\\\"gl_project_path\\\":\\\"erl-omsk/smev-fssp\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45169 user=\"user with id key-147\"\n" + "time=\"2019-06-10T09:23:44+03:00\" level=info msg=\"finished HTTP request\" duration=0.022346368 gitaly_embedded=false method=POST pid=45236 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:44+03:00\" level=error msg=\"Call failed\" body=\"{\\\"status\\\":false,\\\"message\\\":\\\"Your account has been blocked.\\\"}\" code=401 method=POST pid=45236 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:44+03:00\" level=warn msg=\"Access denied\" command=\"git-upload-pack 'kubernetes/heapster-k8s-config.git'\" pid=45236 user=\"user with id key-18\"\n" + "time=\"2019-06-10T09:23:46+03:00\" level=info msg=\"finished HTTP request\" duration=0.019885438 gitaly_embedded=false method=POST pid=45308 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:46+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"erl-omsk/eps-mail-receiver.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-814\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-mail-receiver\\\"},\\\"gl_repository\\\":\\\"project-814\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-mail-receiver\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45308 user=\"user with id key-147\"\n" + "time=\"2019-06-10T09:23:51+03:00\" level=info msg=\"finished HTTP request\" duration=0.025155263 gitaly_embedded=false method=POST pid=45461 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:51+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"erl-omsk/eps-api.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-906\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-api\\\"},\\\"gl_repository\\\":\\\"project-906\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-api\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45461 user=\"user with id key-147\"\n" + "time=\"2019-06-10T09:23:53+03:00\" level=info msg=\"finished HTTP request\" duration=0.0159927 gitaly_embedded=false method=POST pid=45550 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:53+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"uksz/as-ss-stub.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-1644\\\",\\\"gl_project_path\\\":\\\"uksz/as-ss-stub\\\"},\\\"gl_repository\\\":\\\"project-1644\\\",\\\"gl_project_path\\\":\\\"uksz/as-ss-stub\\\",\\\"gl_id\\\":\\\"key-580\\\",\\\"gl_username\\\":\\\"Ext-A.P.Kosarenko\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45550 user=\"user with id key-580\"\n" + "time=\"2019-06-10T09:23:54+03:00\" level=info msg=\"finished HTTP request\" duration=0.014709537 gitaly_embedded=false method=POST pid=45593 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:54+03:00\" level=error msg=\"Call failed\" body=\"{\\\"status\\\":false,\\\"message\\\":\\\"Your account has been blocked.\\\"}\" code=401 method=POST pid=45593 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:54+03:00\" level=warn msg=\"Access denied\" command=\"git-upload-pack 'Docker/example.git'\" pid=45593 user=\"user with id key-18\"\n" + "time=\"2019-06-10T09:23:55+03:00\" level=info msg=\"finished HTTP request\" duration=0.020508204 gitaly_embedded=false method=POST pid=45669 url=\"http://127.0.0.1:8080/api/v4/internal/allowed\"\n" + "time=\"2019-06-10T09:23:55+03:00\" level=info msg=\"executing git command\" command=\"gitaly-upload-pack unix:/var/opt/gitlab/gitaly/gitaly.socket {\\\"repository\\\":{\\\"storage_name\\\":\\\"default\\\",\\\"relative_path\\\":\\\"erl-omsk/eps-digital-signature.git\\\",\\\"git_object_directory\\\":\\\"\\\",\\\"git_alternate_object_directories\\\":[],\\\"gl_repository\\\":\\\"project-785\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-digital-signature\\\"},\\\"gl_repository\\\":\\\"project-785\\\",\\\"gl_project_path\\\":\\\"erl-omsk/eps-digital-signature\\\",\\\"gl_id\\\":\\\"key-147\\\",\\\"gl_username\\\":\\\"Ext-Y.Korop\\\",\\\"git_config_options\\\":[],\\\"git_protocol\\\":null}\" pid=45669 user=\"user with id key-147\""; 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