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 = "(?<=version:\\s\\s\\s\\s\\s\\s\\s\\s)\\d+(\\.\\d+)+"; final String string = "filename: /usr/lib/modules/5.7.7-967.native/kernel/drivers/video/nvidia.ko\n" + "alias: char-major-195-*\n" + "version: 450.57\n" + "supported: external\n" + "license: NVIDIA\n" + "srcversion: CCB2AEF641D4CD7A82E48B3\n" + "alias: pci:v000010DEd*sv*sd*bc03sc02i00*\n" + "alias: pci:v000010DEd*sv*sd*bc03sc00i00*\n" + "depends:\n" + "retpoline: Y\n" + "name: nvidia\n" + "vermagic: 5.7.7-967.native SMP mod_unload\n" + "parm: NvSwitchRegDwords:NvSwitch regkey (charp)\n" + "parm: NvSwitchBlacklist:NvSwitchBlacklist=uuid[,uuid...] (charp)\n" + "parm: nv_cap_enable_devfs:nv_cap_enable_devfs=0 or 1 (int)\n" + "parm: NVreg_ResmanDebugLevel:int\n" + "parm: NVreg_RmLogonRC:int\n" + "parm: NVreg_ModifyDeviceFiles:int\n" + "parm: NVreg_DeviceFileUID:int\n" + "parm: NVreg_DeviceFileGID:int\n" + "parm: NVreg_DeviceFileMode:int\n" + "parm: NVreg_InitializeSystemMemoryAllocations:int\n" + "parm: NVreg_UsePageAttributeTable:int\n" + "parm: NVreg_MapRegistersEarly:int\n" + "parm: NVreg_RegisterForACPIEvents:int\n" + "parm: NVreg_EnablePCIeGen3:int\n" + "parm: NVreg_EnableMSI:int\n" + "parm: NVreg_TCEBypassMode:int\n" + "parm: NVreg_EnableStreamMemOPs:int\n" + "parm: NVreg_EnableBacklightHandler:int\n" + "parm: NVreg_RestrictProfilingToAdminUsers:int\n" + "parm: NVreg_PreserveVideoMemoryAllocations:int\n" + "parm: NVreg_DynamicPowerManagement:int\n" + "parm: NVreg_DynamicPowerManagementVideoMemoryThreshold:int\n" + "parm: NVreg_EnableUserNUMAManagement:int\n" + "parm: NVreg_MemoryPoolSize:int\n" + "parm: NVreg_KMallocHeapMaxSize:int\n" + "parm: NVreg_VMallocHeapMaxSize:int\n" + "parm: NVreg_IgnoreMMIOCheck:int\n" + "parm: NVreg_NvLinkDisable:int\n" + "parm: NVreg_EnablePCIERelaxedOrderingMode:int\n" + "parm: NVreg_RegisterPCIDriver:int\n" + "parm: NVreg_RegistryDwords:charp\n" + "parm: NVreg_RegistryDwordsPerDevice:charp\n" + "parm: NVreg_RmMsg:charp\n" + "parm: NVreg_GpuBlacklist:charp\n" + "parm: NVreg_TemporaryFilePath:charp\n" + "parm: NVreg_AssignGpus:charp"; 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