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

r"
"
g

Test String

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 = "([A-Z0-9-]+)\\.txt:NAME:\\s\\\"module\\s\\w+\\s([0-9/]+)\\\",\\sDESCR:\\s\\\"(.+)\\\""; final String string = "RMAGPGE-PGBP01-01.txt:NAME: \"module R0\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPGE-PGIG01-01.txt:NAME: \"module R0\", DESCR: \"ASR 903 Route Switch Processor 1, Base Scale, 55Gbps\"\n" + "RMAGPGE-PGIG01-01.txt:NAME: \"module R1\", DESCR: \"ASR 903 Route Switch Processor 1, Base Scale, 55Gbps\"\n" + "RMAGPUI-PLIG01-01.txt:NAME: \"module R0\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPUI-PLIG01-01.txt:NAME: \"module R1\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPUI-PLMD00-01.txt:NAME: \"module R0\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPUI-PLMD00-01.txt:NAME: \"module R1\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPUI-PLMI00-01.txt:NAME: \"module R0\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGPUI-PLMI00-01.txt:NAME: \"module R1\", DESCR: \"ASR 900 Route Switch Processor 2, Base Scale, 128Gbps\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/RSP0/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/RSP1/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/0/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/0/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/0\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/0/1\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/3\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/4\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/6\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/0/1/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/1/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/1/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/0\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/1/1\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/3\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/6\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/1/1/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/2/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/2/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/0\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/5\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/2/0/7\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/3/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module 0/3/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/0\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/5\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-CGD01-01.txt:NAME: \"module mau 0/3/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/RSP0/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/RSP1/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/0/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/0/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/0\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/1\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/0/1\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/0\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/3\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/4\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/0/1/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/1/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/1/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/0\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/1\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module 0/1/1\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/0\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/3\", DESCR: \"10GBASE-ZR SFP+, SMF 80km\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-GDL01-01.txt:NAME: \"module mau 0/1/1/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/RSP0/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/RSP1/CPU0\", DESCR: \"ASR9K Route Switch Processor with 440G/slot Fabric and 12GB\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/0/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/0/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/0\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/1\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/0/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/0/1\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/0\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/2\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/3\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/4\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/5\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/6\", DESCR: \"10GBASE-ER 1550nm SMF 40KM\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/0/1/7\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/1/CPU0\", DESCR: \"160G Modular Linecard, Service Edge Optimized\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module 0/1/0\", DESCR: \"ASR 9000 8-port 10GE Modular Port Adapter\"\n" + "RMAGRJO-MRT01-01.txt:NAME: \"module mau 0/1/0/0\", DESCR: \"10GBASE-LR SFP+ Module for SMF\"\n"; final Pattern pattern = Pattern.compile(regex); 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