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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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

"
"
gmi

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 = "([a-zA-Z0-9_]+)(?=:)"; final String string = "[FelixStartLevel] com.adobe.livecycle.content.core-bundle com.adobe.livecycle.content.model.impl.RegisterTypeInternal(3179)] The activate method has thrown an exception (com.adobe.livecycle.content.model.exception.ModelException: ModelException: {Code}-LCC-REP-FCT-002, {Message}-Access denied)\n" + "com.adobe.livecycle.content.model.exception.ModelException: ModelException: {Code}-LCC-REP-FCT-002, {Message}-Access denied\n" + " at com.adobe.livecycle.content.repository.utils.ExceptionUtil.getException(ExceptionUtil.java:52)\n" + " at com.adobe.livecycle.content.repository.utils.ExceptionUtil.getException(ExceptionUtil.java:171)\n" + " at com.adobe.livecycle.content.model.annotation.persister.AnnotationPersister.persistAnnotations(AnnotationPersister.java:156)\n" + " at com.adobe.livecycle.content.model.impl.RegisterTypeInternal.registerTypeInternal(RegisterTypeInternal.java:144)\n" + " at com.adobe.livecycle.content.model.impl.RegisterTypeInternal.registerFileObjectasUnregisteredType(RegisterTypeInternal.java:294)\n" + " at com.adobe.livecycle.content.model.impl.RegisterTypeInternal.activate(RegisterTypeInternal.java:92)\n" + " at sun.reflect.GeneratedMethodAccessor103.invoke(Unknown Source)\n" + " at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)\n" + " at java.lang.reflect.Method.invoke(Method.java:498)\n" + " at org.apache.felix.scr.impl.inject.BaseMethod.invokeMethod(BaseMethod.java:224)\n" + " at org.apache.felix.scr.impl.inject.BaseMethod.access$500(BaseMethod.java:39)\n" + " at org.apache.felix.scr.impl.inject.BaseMethod$Resolved.invoke(BaseMethod.java:617)\n" + " at org.apache.felix.scr.impl.inject.BaseMethod.invoke(BaseMethod.java:501)\n" + " at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:302)\n" + " at org.apache.felix.scr.impl.inject.ActivateMethod.invoke(ActivateMethod.java:294)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.createImplementationObject(SingleComponentManager.java:298)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.createComponent(SingleComponentManager.java:109)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:906)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.getServiceInternal(SingleComponentManager.java:879)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:823)\n" + " at org.apache.felix.framework.ServiceRegistrationImpl.getFactoryUnchecked(ServiceRegistrationImpl.java:347)\n" + " at org.apache.felix.framework.ServiceRegistrationImpl.getService(ServiceRegistrationImpl.java:247)\n" + " at org.apache.felix.framework.ServiceRegistry.getService(ServiceRegistry.java:344)\n" + " at org.apache.felix.framework.Felix.getService(Felix.java:3699)\n" + " at org.apache.felix.framework.BundleContextImpl.getService(BundleContextImpl.java:470)\n" + " at org.apache.felix.scr.impl.manager.SingleRefPair.getServiceObject(SingleRefPair.java:72)\n" + " at org.apache.felix.scr.impl.inject.BindMethod.getServiceObject(BindMethod.java:648)\n" + " at org.apache.felix.scr.impl.manager.DependencyManager.getServiceObject(DependencyManager.java:2201)\n" + " at org.apache.felix.scr.impl.manager.DependencyManager$SingleStaticCustomizer.prebind(DependencyManager.java:1118)\n" + " at org.apache.felix.scr.impl.manager.DependencyManager.prebind(DependencyManager.java:1520)\n" + " at org.apache.felix.scr.impl.manager.AbstractComponentManager.collectDependencies(AbstractComponentManager.java:1006)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.getServiceInternal(SingleComponentManager.java:859)\n" + " at org.apache.felix.scr.impl.manager.SingleComponentManager.getService(SingleComponentManager.java:823)\n" + " at org.apache.felix.framework.ServiceRegistrationImpl.getFactoryUnchecked(ServiceRegistrationImpl.java:347)\n" + " at org.apache.felix.framework.ServiceRegistrationImpl.getService(ServiceRegistrationImpl.java:247)\n" + " at org.apache.felix.framework.ServiceRegistry.getService(ServiceRegistry.java:344)\n" + " at org.apache.felix.framework.Felix.getService(Felix.java:3699"; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.CASE_INSENSITIVE); 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