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"
"
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 = "^(\\w+) (\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}\\.\\d{1,3}):(\\d{1,5})\\@\\d+ ((?:myself,)?[\\w?]+) ([\\w-]+) ([\\d]+) ([\\d]+) ([\\d]+) ([\\w]+) ?([ \\-\\d]+)? ?(\\[[\\d]+-(?:>|<)-[\\w]+\\])?"; final String string = "6535e1a5ba67e01527275299ba4328f26872e3d0 10.229.170.172:7000 slave 81bb21169500bf77638103c9c09583101e475639 0 1597310146695 7 connected\n" + "d2b0b248493fcfbf8522e9546f1057706a18187a 10.229.170.171:7000 slave 2236a749ebf3a8bce1f6ac1ffc3100b28db46604 0 1597310148732 11 connected\n" + "db50d92a23cee951eff8c5d9f64888a9d1a00a13 10.230.140.208:7000 slave f9d94b7ee9cf684199a1b713ae3f37a1de820f52 0 1597310149249 8 connected\n" + "ce7410975901a74c1475c449fd8216cd22168865 10.230.140.208:7001 myself,master - 0 0 10 connected 13505-16383 [13505->-2236a749ebf3a8bce1f6ac1ffc3100b28db46604]\n" + "bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 10.230.140.209:7001 master - 0 1597310145681 5 connected 3277-6553\n" + "518f3da0ab884b2808e278e7d885d77fa7b70abc 10.230.140.210:7000 slave bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 0 1597310143665 5 connected\n" + "f9d94b7ee9cf684199a1b713ae3f37a1de820f52 10.230.140.209:7000 master - 0 1597310144673 8 connected 50-3276\n" + "d2037c152950b5927795d739d1f60d9230bc5243 10.229.170.172:7001 slave ce7410975901a74c1475c449fd8216cd22168865 0 1597310148608 10 connected\n\n\n" + "2236a749ebf3a8bce1f6ac1ffc3100b28db46604 10.230.140.210:7001 master - 0 1597310141662 11 connected 0-49 6554-9880 13108-13220\n" + "81bb21169500bf77638103c9c09583101e475639 10.229.170.171:7001 master - 0 1597310139156 6 connected 9881-13107\n" + "6535e1a5ba67e01527275299ba4328f26872e3d0 10.229.170.172:7000 slave 81bb21169500bf77638103c9c09583101e475639 0 1597310142666 7 connected\n" + "d2b0b248493fcfbf8522e9546f1057706a18187a 10.229.170.171:7000 slave 2236a749ebf3a8bce1f6ac1ffc3100b28db46604 0 1597310143164 11 connected\n" + "db50d92a23cee951eff8c5d9f64888a9d1a00a13 10.230.140.208:7000 slave f9d94b7ee9cf684199a1b713ae3f37a1de820f52 0 1597310141662 8 connected\n" + "ce7410975901a74c1475c449fd8216cd22168865 10.230.140.208:7001 myself,master - 0 0 10 connected 13221-16383 [13221->-2236a749ebf3a8bce1f6ac1ffc3100b28db46604]\n" + "bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 10.230.140.209:7001 master - 0 1597310140659 5 connected 3277-6553\n" + "518f3da0ab884b2808e278e7d885d77fa7b70abc 10.230.140.210:7000 slave bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 0 1597310143665 5 connected\n" + "f9d94b7ee9cf684199a1b713ae3f37a1de820f52 10.230.140.209:7000 master - 0 1597310144673 8 connected 50-3276\n" + "d2037c152950b5927795d739d1f60d9230bc5243 10.229.170.172:7001 slave ce7410975901a74c1475c449fd8216cd22168865 1597310144167 1597310136651 10 connected\n\n" + "ce7410975901a74c1475c449fd8216cd22168865 10.230.140.208:7001 myself,master - 0 0 12 connected 0-49 6554-6842 15254-16383 [6843-<-2236a749ebf3a8bce1f6ac1ffc3100b28db46604]\n" + "bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 10.230.140.209:7001 master - 0 1597319746589 5 connected 3277-6553\n" + "518f3da0ab884b2808e278e7d885d77fa7b70abc 10.230.140.210:7000 slave bf6f4d7f5330fe134a575bcf7e36fd012b4a5cf4 0 1597319749595 5 connected\n" + "f9d94b7ee9cf684199a1b713ae3f37a1de820f52 10.230.140.209:7000 master - 0 1597319746089 8 connected 50-3276\n" + "d2037c152950b5927795d739d1f60d9230bc5243 10.229.170.172:7001 slave ce7410975901a74c1475c449fd8216cd22168865 0 1597319747590 12 connected\n\n" + "2114d318b6bff84367748b0af1480414625db481 10.225.129.237:7000@17000 slave 17a137f8c8ab3886abf9ef756a9e46ce00b3db46 0 1597323334000 8 connected\n" + "f7b8bc2f99e217a9aa33165771d63ac00130bf06 10.225.129.236:7000@17000 slave 29accc30f88be4c5a1b5c316ef4a07db11e773ca 0 1597323335000 1 connected\n" + "29accc30f88be4c5a1b5c316ef4a07db11e773ca 10.225.129.235:7000@17000 myself,master - 0 1597323336000 1 connected 0-2730\n" + "a582a8683f6ba747ec8b1ae959c2aba2009c6fec 10.225.129.235:7001@17001 slave 9445f535348daf42827d0610b42a2f6f67c8c672 0 1597323337133 7 connected\n" + "9445f535348daf42827d0610b42a2f6f67c8c672 10.225.129.240:7001@17001 master - 0 1597323336533 7 connected 13655-16383"; 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