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

/
/
g

Test String

Substitution

Processing...

Code Generator

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "\\s(\\w*)Command\\.Register\\((([\\S]*,([^;\\n\\r])*)+)typeof\\((.*)Values\\)\\);"; final String string = "public static readonly SimpleCommand ReadTemperatureCommand =\n" + " SimpleCommand.Register(ReadTemperatureCommandId, \"ReadTemperature\", \"showtemp.py\", \"\", 5, typeof(TemperatureListCommandResultProcessor), typeof(TemperatureListDeviceValues));\n\n" + " public static readonly SimpleCommand GetDataType1Command =\n" + " SimpleCommand.Register(\n" + " GetDataType1CommandTypeId,\n" + " \"GetData\",\n" + " \"HttpClient2.py\",\n" + " @\"\"\"/data/ajax.txt?CAN=1&HASH=00200403&TYPE=1\"\" \"\"GET\"\" \"\"\"\"\",\n" + " 5,\n" + " typeof(SunwaysSolarInverterDataType1CommandResultProcessor),\n" + " typeof(SunwaysSolarInverterDeviceValues));\n\n" + "public static readonly ArgumentedCommand UpdateAsyncCommandsCommand =\n" + " ArgumentedCommand.Register(\n" + " UpdateAsyncCommandsCommandId,\n" + " \"UpdateAsyncCommands\",\n" + " \"UpdateAsyncCommands.py\",\n" + " \"\",\n" + " 5,\n" + " UpdateAsyncCommandsCreateArguments,\n" + " new[] { typeof(AsynchronousCommand[]) },\n" + " typeof(UpdateAsyncCommandsCommandResultProcessor),\n" + " typeof(GridboxCommunicationObjectValues));\n\n\n\n" + "public static readonly SimpleDynamicObjectAttribute<bool> AsynchronousCommandsChangedProperty =\n" + " SimpleDynamicObjectAttribute<bool>.Register(\"AsynchronousCommandsChanged\", false, typeof(BusyGridObjectValues), false, false);\n\n" + "public static readonly SimpleDynamicObjectAttribute<string> MailProperty =\n" + " SimpleDynamicObjectAttribute<string>.Register(\"Mail\", typeof(DefaultUserValues));\n\n" + "public static readonly ProtectedSimpleDynamicObjectAttribute<int> PasswordStorageMethodVersionProperty =\n" + " ProtectedSimpleDynamicObjectAttribute<int>.Register(\"PasswordStorageMethodVersion\", 2, typeof(DefaultUserValues));\n\n" + "public static readonly ListSetDynamicObjectAttribute<string> LocalIpNetworksProperty =\n" + " ListSetDynamicObjectAttribute<string>.Register(\"LocalIpNetworks\", typeof(GridboxCommunicationObjectValues));\n\n" + "public static readonly DictionaryDynamicObjectAttribute<Guid, GridObjectTypeContentFilter> ContentFiltersProperty =\n" + " DictionaryDynamicObjectAttribute<Guid, GridObjectTypeContentFilter>.Register(\"ContentFilters\", typeof(DefaultContentFilterValues));\n\n" + " public static readonly StrongGridObjectReference ContentFilterListContentFilterIdProperty =\n" + " StrongGridObjectReference.Register(\"ContentFilterListContentFilterId\", new Guid(\"ce06d088-1b5e-4cab-98d2-b0fd63bc0d5b\"), typeof(ContentFilterValues));\n\n" + " public static readonly GridObjectReference ContentFilterListContentFilterIdProperty =\n" + " GridObjectReference.Register(\"ContentFilterListContentFilterId\", new Guid(\"ce06d088-1b5e-4cab-98d2-b0fd63bc0d5b\"), typeof(ContentFilterValues));\n\n" + " public static readonly GridObjectReference ContentFilterListContentFilterIdProperty =\n" + " GridObjectReference.Register(\"ContentFilterListContentFilterId\", new Guid(\"ce06d088-1b5e-4cab-98d2-b0fd63bc0d5b\"), typeof(ContentFilterValues));\n\n" + "public static readonly GridObjectReferenceList PermissionIdsProperty =\n" + " GridObjectReferenceList.Register(\"PermissionIds\", typeof(DefaultRoleValues));"; final String subst = "GridObjectModel.Register$1Reference$2($3, $4TypeIdString);"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceAll(subst); System.out.println("Substitution result: " + result); } }

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