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

/
/

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 = "(?<date>\\[.*?\\]) (.*?) ((.|\\n*)*)"; final String string = "[2022-07-22 09:53:27,793] INFO KafkaConfig values:\n" + " advertised.host.name = null\n" + " advertised.listeners = INTERNAL://0.0.0.0:9092,BROKER://0.0.0.0:9091,CLIENT://0.0.0.0:9093\n" + " advertised.port = null\n" + " alter.config.policy.class.name = null\n" + " alter.log.dirs.replication.quota.window.num = 11\n" + " alter.log.dirs.replication.quota.window.size.seconds = 1\n" + " authorizer.class.name =\n" + " auto.create.topics.enable = true\n" + " auto.leader.rebalance.enable = true\n" + " background.threads = 10\n" + " broker.id = 0\n" + " broker.id.generation.enable = true\n" + " broker.rack = null\n" + " client.quota.callback.class = null\n" + " compression.type = producer\n" + " connection.failed.authentication.delay.ms = 100\n" + " connections.max.idle.ms = 600000\n" + " connections.max.reauth.ms = 0\n" + " control.plane.listener.name = null\n" + " controlled.shutdown.enable = true\n" + " controlled.shutdown.max.retries = 3\n" + " controlled.shutdown.retry.backoff.ms = 5000\n" + " controller.socket.timeout.ms = 30000\n" + " create.topic.policy.class.name = null\n" + " default.replication.factor = 1\n" + " delegation.token.expiry.check.interval.ms = 3600000\n" + " delegation.token.expiry.time.ms = 86400000\n" + " delegation.token.master.key = null\n" + " delegation.token.max.lifetime.ms = 604800000\n" + " delete.records.purgatory.purge.interval.requests = 1\n" + " delete.topic.enable = true\n" + " fetch.purgatory.purge.interval.requests = 1000\n" + " group.initial.rebalance.delay.ms = 3000\n" + " group.max.session.timeout.ms = 1800000\n" + " group.max.size = 2147483647\n" + " group.min.session.timeout.ms = 6000\n" + " host.name =\n" + " inter.broker.listener.name = BROKER\n" + " inter.broker.protocol.version = 2.3-IV1\n" + " kafka.metrics.polling.interval.secs = 10\n" + " kafka.metrics.reporters = []\n" + " leader.imbalance.check.interval.seconds = 300\n" + " leader.imbalance.per.broker.percentage = 10\n" + " listener.security.protocol.map = INTERNAL:PLAINTEXT,BROKER:PLAINTEXT,CLIENT:PLAINTEXT\n" + " listeners = INTERNAL://:9092,BROKER://:9091,CLIENT://:9093\n" + " log.cleaner.backoff.ms = 15000\n" + " log.cleaner.dedupe.buffer.size = 134217728\n" + " log.cleaner.delete.retention.ms = 86400000\n" + " log.cleaner.enable = true\n" + " log.cleaner.io.buffer.load.factor = 0.9\n" + " log.cleaner.io.buffer.size = 524288\n" + " log.cleaner.io.max.bytes.per.second = 1.7976931348623157E308\n" + " log.cleaner.max.compaction.lag.ms = 9223372036854775807\n" + " log.cleaner.min.cleanable.ratio = 0.5\n" + " log.cleaner.min.compaction.lag.ms = 0\n" + " log.cleaner.threads = 1\n" + " log.cleanup.policy = [delete]\n" + " log.dir = /tmp/kafka-logs\n" + " log.dirs = /var/lib/kafka\n" + " log.flush.interval.messages = 9223372036854775807\n" + " log.flush.interval.ms = null\n" + " log.flush.offset.checkpoint.interval.ms = 60000\n" + " log.flush.scheduler.interval.ms = 9223372036854775807\n" + " log.flush.start.offset.checkpoint.interval.ms = 60000\n" + " log.index.interval.bytes = 4096\n" + " log.index.size.max.bytes = 10485760\n" + " log.message.downconversion.enable = true\n" + " log.message.format.version = 2.3-IV1\n" + " log.message.timestamp.difference.max.ms = 9223372036854775807\n" + " log.message.timestamp.type = CreateTime\n" + " log.preallocate = false\n" + " log.retention.bytes = -1\n" + " log.retention.check.interval.ms = 300000\n" + " log.retention.hours = 120\n" + " log.retention.minutes = null\n" + " log.retention.ms = null\n" + " log.roll.hours = 168\n" + " log.roll.jitter.hours = 0\n" + " log.roll.jitter.ms = null\n" + " log.roll.ms = null\n" + " log.segment.bytes = 1073741824\n" + " log.segment.delete.delay.ms = 60000\n" + " max.connections = 2147483647\n" + " max.connections.per.ip = 2147483647\n" + " max.connections.per.ip.overrides =\n" + " max.incremental.fetch.session.cache.slots = 1000\n" + " message.max.bytes = 1000012\n" + " metric.reporters = []\n" + " metrics.num.samples = 2\n" + " metrics.recording.level = INFO\n" + " metrics.sample.window.ms = 30000\n" + " min.insync.replicas = 1\n" + " num.io.threads = 8\n" + " num.network.threads = 3\n" + " num.partitions = 1\n" + " num.recovery.threads.per.data.dir = 1\n" + " num.replica.alter.log.dirs.threads = null\n" + " num.replica.fetchers = 1\n" + " offset.metadata.max.bytes = 4096\n" + " offsets.commit.required.acks = -1\n" + " offsets.commit.timeout.ms = 5000\n" + " offsets.load.buffer.size = 5242880\n" + " offsets.retention.check.interval.ms = 600000\n" + " offsets.retention.minutes = 10080\n" + " offsets.topic.compression.codec = 0\n" + " offsets.topic.num.partitions = 50\n" + " offsets.topic.replication.factor = 1\n" + " offsets.topic.segment.bytes = 104857600\n" + " password.encoder.cipher.algorithm = AES/CBC/PKCS5Padding\n" + " password.encoder.iterations = 4096\n" + " password.encoder.key.length = 128\n" + " password.encoder.keyfactory.algorithm = null\n" + " password.encoder.old.secret = null\n" + " password.encoder.secret = null\n" + " port = 9092\n" + " principal.builder.class = null\n" + " producer.purgatory.purge.interval.requests = 1000\n" + " queued.max.request.bytes = -1\n" + " queued.max.requests = 500\n" + " quota.consumer.default = 9223372036854775807\n" + " quota.producer.default = 9223372036854775807\n" + " quota.window.num = 11\n" + " quota.window.size.seconds = 1\n" + " replica.fetch.backoff.ms = 1000\n" + " replica.fetch.max.bytes = 1048576\n" + " replica.fetch.min.bytes = 1\n" + " replica.fetch.response.max.bytes = 10485760\n" + " replica.fetch.wait.max.ms = 500\n" + " replica.high.watermark.checkpoint.interval.ms = 5000\n" + " replica.lag.time.max.ms = 10000\n" + " replica.socket.receive.buffer.bytes = 65536\n" + " replica.socket.timeout.ms = 30000\n" + " replication.quota.window.num = 11\n" + " replication.quota.window.size.seconds = 1\n" + " request.timeout.ms = 30000\n" + " reserved.broker.max.id = 1000\n" + " sasl.client.callback.handler.class = null\n" + " sasl.enabled.mechanisms = [GSSAPI]\n" + " sasl.jaas.config = null\n" + " sasl.kerberos.kinit.cmd = /usr/bin/kinit\n" + " sasl.kerberos.min.time.before.relogin = 60000\n" + " sasl.kerberos.principal.to.local.rules = [DEFAULT]\n" + " sasl.kerberos.service.name = null\n" + " sasl.kerberos.ticket.renew.jitter = 0.05\n" + " sasl.kerberos.ticket.renew.window.factor = 0.8\n" + " sasl.login.callback.handler.class = null\n" + " sasl.login.class = null\n" + " sasl.login.refresh.buffer.seconds = 300\n" + " sasl.login.refresh.min.period.seconds = 60\n" + " sasl.login.refresh.window.factor = 0.8\n" + " sasl.login.refresh.window.jitter = 0.05\n" + " sasl.mechanism.inter.broker.protocol = GSSAPI\n" + " sasl.server.callback.handler.class = null\n" + " security.inter.broker.protocol = PLAINTEXT\n" + " socket.receive.buffer.bytes = 102400\n" + " socket.request.max.bytes = 104857600\n" + " socket.send.buffer.bytes = 102400\n" + " ssl.cipher.suites = []\n" + " ssl.client.auth = none\n" + " ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1]\n" + " ssl.endpoint.identification.algorithm = https\n" + " ssl.key.password = null\n" + " ssl.keymanager.algorithm = SunX509\n" + " ssl.keystore.location = null\n" + " ssl.keystore.password = null\n" + " ssl.keystore.type = JKS\n" + " ssl.principal.mapping.rules = [DEFAULT]\n" + " ssl.protocol = TLS\n" + " ssl.provider = null\n" + " ssl.secure.random.implementation = null\n" + " ssl.trustmanager.algorithm = PKIX\n" + " ssl.truststore.location = null\n" + " ssl.truststore.password = null\n" + " ssl.truststore.type = JKS\n" + " transaction.abort.timed.out.transaction.cleanup.interval.ms = 60000\n" + " transaction.max.timeout.ms = 900000\n" + " transaction.remove.expired.transaction.cleanup.interval.ms = 3600000\n" + " transaction.state.log.load.buffer.size = 5242880\n" + " transaction.state.log.min.isr = 2\n" + " transaction.state.log.num.partitions = 50\n" + " transaction.state.log.replication.factor = 3\n" + " transaction.state.log.segment.bytes = 104857600\n" + " transactional.id.expiration.ms = 604800000\n" + " unclean.leader.election.enable = false\n" + " zookeeper.connect = 0.0.0.0:2181\n" + " zookeeper.connection.timeout.ms = 18000\n" + " zookeeper.max.in.flight.requests = 10\n" + " zookeeper.session.timeout.ms = 6000\n" + " zookeeper.set.acl = false\n" + " zookeeper.sync.time.ms = 2000\n" + " (kafka.server.KafkaConfig)\n" + "[2022-07-22 09:53:27,840] ERROR Fatal error during SupportedServerStartable startup. Prepare to shutdown (io.confluent.support.metrics.SupportedKafka)\n" + "java.lang.IllegalArgumentException: requirement failed: advertised.listeners cannot use the nonroutable meta-address 0.0.0.0. Use a routable IP address.\n" + " at scala.Predef$.require(Predef.scala:224)\n" + " at kafka.server.KafkaConfig.validateValues(KafkaConfig.scala:1492)\n" + " at kafka.server.KafkaConfig.<init>(KafkaConfig.scala:1460)\n" + " at kafka.server.KafkaConfig.<init>(KafkaConfig.scala:1114)\n" + " at kafka.server.KafkaConfig$.fromProps(KafkaConfig.scala:1094)\n" + " at kafka.server.KafkaConfig$.fromProps(KafkaConfig.scala:1091)\n" + " at kafka.server.KafkaConfig.fromProps(KafkaConfig.scala)\n" + " at io.confluent.support.metrics.SupportedServerStartable.<init>(SupportedServerStartable.java:52)\n" + " at io.confluent.support.metrics.SupportedKafka.main(SupportedKafka.java:45)"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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