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 = "[\\s]*([\\/+\\s\\w@'\\,\\.()\\-\\*\\-\\>\\<\\_\\\"]*)?[\\n]*UFUNCTION[(]([\\w<>\\s\\(\\)\\=\\,\\\"\\| ]*|\\n]*)[\\)]\\n\\s(virtual)*\\s*(static)*\\s*(\\w+\\&?\\*?)\\s(\\w+)[(]([\\w<>\\s,&\\*]*|\\n]*)[)][\\s]*([const]*)"; final String string = "// Fill out your copyright notice in the Description page of Project Settings.\n\n" + "#pragma once\n\n" + "#include \"CoreMinimal.h\"\n" + "#include \"GM_Stepper.h\"\n" + "#include \"Kismet/BlueprintFunctionLibrary.h\"\n" + "#include \"StepperTypes.h\"\n" + "#include \"Encoder/EncodeData.h\"\n" + "#include \"Components/TextBlock.h\"\n" + "#include \"BFL_Stepper.generated.h\"\n\n\n\n" + "/**\n" + " * \n" + " */\n" + "UCLASS()\n" + "class STEPPER_API UBFL_Stepper : public UBlueprintFunctionLibrary\n" + "{\n" + " GENERATED_BODY()\n\n" + "public:\n" + " // Returns a copy of the current rendering LogPacket\n" + " // For use ONLY during render time\n" + " // Will be invalid otherwise\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Core\")\n" + " static FLogPacket& GetCurrentLogPacket(bool& Success);\n\n" + " // Updates the log packet sources in memory\n" + " UFUNCTION(BlueprintCallable, Category = \"Stepper|Core\")\n" + " static bool UpdatePacket(FLogPacket NewPacket);\n\n" + " // Returns a copy of the requested MetaData from the relevant core\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Core\")\n" + " static FGenericMetaTag GetMetaTag(FLogPacket ReferencePacket, FName MetaTag, bool& bIsValid);\n" + " \n" + " // Returns a copy of the requested MetaData from the supplied packet\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Core\")\n" + " static FGenericMetaTag GetMetaTag_Explicit(FLogPacket ReferencePacket, FName MetaTag, bool& bIsValid);\n\n" + " // Returns a logLine for this LogPacket by a LineId\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Core\")\n" + " static bool GetLogLineInId(FLogPacket ReferencePacket, int32 inId, FActionLine& LineData);\n\n" + " // Returns a logLine for this LogPacket by seeking from a specific line\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Core\")\n" + " static bool GetNextActionByType(FLogPacket ReferencePacket, FAction RefAction, FName NextActionName, bool bShouldDebug, FActionLine& Action);\n" + " \n" + " // Updates the LogPacket in memory and text file \n" + " UFUNCTION(BlueprintCallable, Category = \"Stepper|Core\")\n" + " static void UpdateGenericTag(FLogPacket ReferencePacket, FGenericMetaTag MetaTag);\n\n" + " // Get the saved user settings\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|User Settings\")\n" + " static bool GetUserSettings(FUserSettings& Settings);\n\n" + " // Get the saved capture resolution\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|User Settings\")\n" + " static FIntPoint GetCaptureResolution();\n\n" + " // Get the saved output resolution\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|User Settings\")\n" + " static FIntPoint GetOutputResolution();\n\n" + " // Get the root output folder for this log\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|User Settings\")\n" + " static FString GetLogOutputFolder();\n\n" + " // Gets the saved resources folder\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|User Settings\")\n" + " static FString GetResourcesFolder();\n\n" + " // Get a reference to the active UStepperObject\n" + " // Can be nullptr\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Statics\")\n" + " static UStepperCore* GetStepper();\n\n" + " // Get the currently rendered stepper frame number\n" + " // Return -1 if not rendering\n" + " UFUNCTION(BlueprintPure, Category = \"Stepper|Statics\")\n" + " static int32 GetStepperFrame();\n\n" + " // Checks if a file is of type \"png\", \"jpg\", \"mp4\" or \"mov\"\n" + " UFUNCTION(BlueprintPure)\n" + " static bool bIsMediaFile(FString FileName);\n\n" + " // Get the language of the inputted log packet\n" + " UFUNCTION(BlueprintPure)\n" + " static FString GetLogLanguage(FLogPacket LogPacket);\n\n" + " // Get the packet's framerate\n" + " UFUNCTION(BlueprintPure, meta=(CompactNodeTitle=\"FR\", Keywords = \"FrameRate, Frame, Rate\"))\n" + " static FFrameRate GetPacketFrameRate(FLogPacket Packet);\n" + " // Get the rendered framerate\n" + " UFUNCTION(BlueprintPure, meta=(CompactNodeTitle=\"FR\", Keywords = \"FrameRate, Frame, Rate\"))\n" + " static bool GetRenderedFrameRate(FFrameRate& FrameRate);\n" + " // Get the packet's start timecode\n" + " UFUNCTION(BlueprintPure, meta=(CompactNodeTitle=\"STC\", Keywords = \"Timecode, Time, Code, TC\"))\n" + " static FTimecode GetPacketStartTimecode(FLogPacket Packet);\n" + " // Get the packet's end timecode\n" + " UFUNCTION(BlueprintPure, meta=(CompactNodeTitle=\"ETC\", Keywords = \"Timecode, Time, Code, TC\"))\n" + " static FTimecode GetPacketEndTimecode(FLogPacket Packet);\n" + " //Get the timecode data struct from the currently loaded LogPackt's MetaData\n" + " UFUNCTION(BlueprintCallable, BlueprintPure, Category = \"Stepper|XML|Helpers\")\n" + " static FTimecodeData GetPacketTimecodeData(FLogPacket Packet);\n\n\n" + " UFUNCTION()\n" + " static bool bIsDllLoaded(FString DllName);\n\n" + " // Get a reference to the active game mode\n" + " UFUNCTION(BlueprintCallable)\n" + " static AGM_Stepper* GetGameMode();\n\n" + " UFUNCTION()\n" + " static ELogRenderStatus QtChangeFile(FLogPacket& LogPacket, FCameraData& CameraData, int32 Iteration);\n" + " UFUNCTION()\n" + " static ELogRenderStatus QtChangeFile_Scatter(FLogPacket& LogPacket, FCameraData& CameraData, int32 ScatterIndex, FName ScatterTag, FTimecode ClipTc, int32 Iteration);\n" + " UFUNCTION()\n" + " static ELogRenderStatus RunQtBat(FString BatLoc, FString Dir);\n\n" + " UFUNCTION()\n" + " static int CheckLine(FString Line);\n" + " // Break a TextBox's text into lines\n" + " UFUNCTION(BlueprintCallable)\n" + " static void BreakTextBox(UTextBlock* TextBox, int32 MaxLineSize);\n\n" + " //Takes a snapshot of a widget and returns it as a render target\n" + " UFUNCTION(BlueprintCallable, Category = \"Stepper|Helpers\", meta=(DisplayName=\"Render Target From Widget With Alpha\"))\n" + " static UTextureRenderTarget2D* RtFromWidget_Alpha(UUserWidget* const Widget, FVector2D Size);\n\n" + " //Adds a prefix 0 for numbers below 10 (i.e 6 -> 06)\n" + " UFUNCTION(BlueprintCallable, BlueprintPure, Category = \"Stepper|Helpers\")\n" + " static void IntToPaddedString(int32 Int, FString& PaddedString);\n\n\n" + " \n" + "};\n"; 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