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 = "^Cisco Catalyst.*AC Power Supply$"; final String string = "Cisco Catalyst 9500 Series Chassis\n" + "Cisco Catalyst 9500 Series Power Supply Bay Module Container\n" + "Cisco Catalyst 9500 Series Power Supply Bay Module Container\n" + "Cisco Catalyst 9500 Series Fan Tray Bay Module Container\n" + "Cisco Catalyst 9500 Series 650W AC Power Supply\n" + "Cisco Catalyst 9500 Series Power Supply\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series 650W AC Power Supply\n" + "Cisco Catalyst 9500 Series Power Supply\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan Tray\n" + "Cisco Catalyst 9500 Series Fan Tray\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Fan\n" + "Cisco Catalyst 9500 Series Router\n" + "PSOC-MB_0: VOU\n" + "PSOC-MB_1: VOU\n" + "PSOC-MB_2: VOU\n" + "PSOC-MB_3: VOU\n" + "PSOC-MB_4: VOU\n" + "PSOC-MB_5: VOU\n" + "PSOC-MB_7: VOU\n" + "PSOC-MB_8: VOU\n" + "PSOC-MB_9: VOU\n" + "PSOC-MB_10: VO\n" + "3570MB1_0: VOU\n" + "3570MB2_0: VOU\n" + "3570MB3_0: VOU\n" + "35215MB1_0: VO\n" + "35215MB2_0: VO\n" + "Temp: Outlet_A\n" + "Temp: Outlet_B\n" + "Temp: Inlet_A\n" + "Temp: Inlet_B\n" + "Temp: UADP_0_0\n" + "Temp: UADP_0_1\n" + "Temp: UADP_0_2\n" + "Temp: UADP_0_3\n" + "Temp: UADP_0_4\n" + "Temp: UADP_0_5\n" + "Temp: UADP_0_6\n" + "Temp: UADP_0_7\n" + "Temp: UADP_0_8\n" + "PSOC-DB_1: VOU\n" + "PSOC-DB_2: VOU\n" + "PSOC-DB_4: VOU\n" + "PSOC-DB_5: VOU\n" + "PSOC-DB_7: VOU\n" + "PSOC-DB_8: VOU\n" + "PSOC-DB_11: VO\n" + "3570DB1_0: VOU\n" + "3570DB2_0: VOU\n" + "3570DB3_0: VOU\n" + "Temp: Coretemp\n" + "Temp: OutletDB\n" + "Intel CPU x86-64\n" + "USB Port\n" + "TwentyFiveGigE1/0/1 Container\n" + "TwentyFiveGigE1/0/2 Container\n" + "TwentyFiveGigE1/0/3 Container\n" + "TwentyFiveGigE1/0/4 Container\n" + "TwentyFiveGigE1/0/5 Container\n" + "TwentyFiveGigE1/0/6 Container\n" + "TwentyFiveGigE1/0/7 Container\n" + "TwentyFiveGigE1/0/8 Container\n" + "TwentyFiveGigE1/0/9 Container\n" + "TwentyFiveGigE1/0/10 Container\n" + "TwentyFiveGigE1/0/11 Container\n" + "TwentyFiveGigE1/0/12 Container\n" + "TwentyFiveGigE1/0/13 Container\n" + "TwentyFiveGigE1/0/14 Container\n" + "TwentyFiveGigE1/0/15 Container\n" + "TwentyFiveGigE1/0/16 Container\n" + "TwentyFiveGigE1/0/17 Container\n" + "TwentyFiveGigE1/0/18 Container\n" + "TwentyFiveGigE1/0/19 Container\n" + "TwentyFiveGigE1/0/20 Container\n" + "TwentyFiveGigE1/0/21 Container\n" + "TwentyFiveGigE1/0/22 Container\n" + "TwentyFiveGigE1/0/23 Container\n" + "TwentyFiveGigE1/0/24 Container\n" + "HundredGigE1/0/25 Container\n" + "HundredGigE1/0/26 Container\n" + "HundredGigE1/0/27 Container\n" + "HundredGigE1/0/28 Container\n" + "SFP+ 10GBASE-SR\n" + "Twe1/0/1 Module Temperature Sensor\n" + "Twe1/0/1 Supply Voltage Sensor\n" + "Twe1/0/1 Bias Current Sensor\n" + "Twe1/0/1 Transmit Power Sensor\n" + "Twe1/0/1 Receive Power Sensor\n" + "GE T\n" + "GE T\n" + "SFP+ 10GBASE-SR"; 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