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 = "(\\/.{1,}:.+|^Null|^VLAN)"; final String string = "GigaEthernet0/5\n" + "GigaEthernet0/6\n" + "GigaEthernet0/45\n" + "GigaEthernet0/3\n" + "GigaEthernet0/1\n" + "GigaEthernet0/2\n" + "VLAN10\n" + "EPON110/111\n" + "EPON0/2\n" + "EPON0/3\n" + "EPON0/4\n" + "EPON0/1:1\n" + "EPON0/10:2\n" + "EPON0/20:3\n" + "EPON0/1:4\n" + "EPON0/1:5\n" + "EPON0/1:6\n" + "EPON0/1:7\n" + "EPON0/111:8\n" + "EPON0/1:9\n" + "EPON0/1:10\n" + "EPON0/1:11\n" + "EPON0/1:12\n" + "EPON0/1:13\n" + "EPON0/1:14\n" + "EPON0/1:15\n" + "EPON0/1:16\n" + "EPON0/1:17\n" + "EPON0/1:18\n" + "EPON0/1:19\n" + "EPON0/1:20\n" + "EPON0/1:21\n" + "EPON0/1:22\n" + "EPON0/1:23\n" + "EPON0/1:24\n" + "EPON0/1:25\n" + "EPON0/1:26\n" + "EPON0/1:27\n" + "EPON0/1:28\n" + "EPON0/1:29\n" + "EPON0/1:30\n" + "EPON0/1:31\n" + "EPON0/1:32\n" + "EPON0/1:33\n" + "EPON0/1:34\n" + "EPON0/1:35\n" + "EPON0/1:36\n" + "EPON0/1:37\n" + "EPON0/1:38\n" + "EPON0/1:39\n" + "EPON0/1:40\n" + "EPON0/1:41\n" + "EPON0/1:42\n" + "EPON0/2:1\n" + "EPON0/2:2\n" + "EPON0/2:3\n" + "EPON0/2:4\n" + "EPON0/2:5\n" + "EPON0/2:6\n" + "EPON0/2:7\n" + "EPON0/2:8\n" + "EPON0/2:9\n" + "EPON0/2:10\n" + "EPON0/2:11\n" + "EPON0/2:12\n" + "EPON0/2:13\n" + "EPON0/2:14\n" + "EPON0/2:15\n" + "EPON0/2:16\n" + "EPON0/2:17\n" + "EPON0/2:18\n" + "EPON0/2:19\n" + "EPON0/2:20\n" + "EPON0/2:21\n" + "EPON0/3:1\n" + "EPON0/3:2\n" + "EPON0/3:3\n" + "EPON0/3:4\n" + "EPON0/3:5\n" + "EPON0/3:6\n" + "EPON0/3:7\n" + "EPON0/3:8\n" + "EPON0/3:9\n" + "EPON0/3:10\n" + "EPON0/3:11\n" + "EPON0/3:12\n" + "EPON0/3:13\n" + "EPON0/3:14\n" + "EPON0/3:15\n" + "EPON0/3:16\n" + "EPON0/3:17\n" + "EPON0/3:18\n" + "EPON0/3:19\n" + "EPON0/3:20\n" + "EPON0/3:21\n" + "EPON0/3:22\n" + "EPON0/3:23\n" + "EPON0/3:24\n" + "EPON0/3:27\n" + "EPON0/3:28\n" + "EPON0/3:29\n" + "EPON0/3:64\n" + "EPON0/4:1\n" + "EPON0/4:2\n" + "EPON0/4:3\n" + "EPON0/4:4\n" + "EPON0/4:5\n" + "EPON0/4:6\n" + "EPON0/4:7\n" + "EPON0/4:8\n" + "EPON0/4:9\n" + "EPON0/4:10\n" + "EPON0/4:11\n" + "EPON0/4:12\n" + "EPON0/4:13\n" + "EPON0/4:14\n" + "EPON0/4:15\n" + "EPON0/4:16\n" + "EPON0/4:17\n" + "EPON0/4:18\n" + "EPON0/4:19\n" + "EPON0/4:20\n" + "EPON0/4:21\n" + "EPON0/4:22\n" + "EPON0/4:23\n" + "EPON0/4:24\n" + "EPON0/4:25\n" + "EPON0/4:26\n" + "EPON0/4:27\n" + "EPON0/4:28\n" + "EPON0/4:29\n" + "EPON0/4:30\n" + "EPON0/4:31\n" + "EPON0/4:32\n" + "EPON0/4:33\n" + "EPON0/4:34\n" + "EPON0/4:35\n" + "EPON0/4:36\n" + "EPON0/4:37\n" + "EPON0/4:38\n" + "EPON0/4:39\n" + "EPON0/4:40\n" + "EPON0/4:41\n" + "EPON0/4:42\n" + "EPON0/4:43\n" + "EPON0/4:44\n" + "EPON0/4:45\n" + "EPON0/4:46\n" + "EPON0/4:47\n" + "EPON0/4:48\n" + "EPON0/4:49\n" + "EPON0/4:50\n" + "EPON0/4:51\n" + "EPON0/4:52\n" + "EPON0/4:53\n" + "EPON0/4:54"; 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