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

/
/

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 = "(?:opc.tcp|https|http):\\/\\/(\\S+):\\d+[\\/\\w]*"; final String string = "https://198.10.157.14:4814/fdggfh/fdhgdsf/gnhdfg\n\n" + "opc.tcp://198.10.157.14:4814/fdggfh/fdhgdsf/gnhdfg\n\n\n" + "address 192.168.1.1\n" + " netmask 255.255.255.0\n" + " gateway 192.168.1.254\n\n" + "=[\\w\\W]*(auto[\\w\\W]*eth2\\s+inet\\s+(dhcp|static)\\s*((?:address\\s+\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})\\s+(?:netmask\\s+\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})\\s+(?:gateway\\s+(\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})))?)\n\n" + "auto eth2\n" + "iface eth2 inet static\n" + " address 192.168.1.1\n" + " netmask 255.255.255.0\n" + " gateway 192.168.1.254\n" + "pre-up /sbin/ifconfig $IFACE mtu 1450\n\n" + "auto eth3\n" + "iface eth3 inet static\n" + " address 192.168.1.1\n" + " netmask 255.255.255.0\n" + " gateway 192.168.1.254\n\n" + "= ([\\d\\.]+)(\\w?)\\s+\\d+%.*\n" + "/dev/sda1 ff 55 7sg233 fgd 3.7G 4.0K 3.7G 0% /mnt/sda1 \n\n\n" + " <?xml version=\"1.0\" encoding= \"utf-8\"?>\n" + "<confi guration>\n\n" + "[\\w\\W]*(auto[\\w\\W]*eth2\\s+inet\\s+(dhcp|static)\\s+((?:address\\s+\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})?\\s*(?:netmask\\s+\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3})?\\s*(?:gateway\\s+(\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}))?)?\\s+(pre-up \\/sbin\\/ifconfig \\$IFACE mtu \\d{3,4}\\s+))"; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); if (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