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
Processing...

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 = "((?<ID>\\d+)\\s(?<LunName>[a-zA-Z0-9_]+)\\s+(?<ProvisionType>tpvv)\\s(?<vvType>base)\\s(?<CopyOf>---)\\s+(?<BsId>\\d+)\\s+(?<ReadWrite>RW|RO)\\s(?<State>normal|degraded)\\s+(?<Adm>\\d+)\\s+(?<Snp>\\d+)\\s+(?<Usr>\\d+)\\s+?(?<VSize>\\d+))"; final String string = " -------Rsvd(MB)-------- --(MB)--\n" + " Id Name Prov Type CopyOf BsId Rd -Detailed_State- Adm Snp Usr VSize\n" + "4134 VMFS_L021_NR_INFRA01 tpvv base --- 4134 RW normal 28928 6321024 9545088 16777216\n" + "4139 VMFS_L033_R_OPS01 tpvv base --- 4139 RW normal 1792 259456 771072 1277952\n" + " 135 VMFS_L041_REPL_7400 tpvv base --- 135 RW normal 14080 4664704 6828288 8241152\n" + "4168 VMFS_L050_R_DEV01 tpvv base --- 4168 RW normal 6912 633472 3564544 6291456\n" + "5798 VMFS_L056_R_DMS01 tpvv base --- 5798 RW normal 1536 341632 508928 819200\n" + "4135 VMFS_L060_R_CYPS01 tpvv base --- 4135 RW normal 1280 120448 295936 1572864\n" + "4136 VMFS_L061_NR_CYPS01 tpvv base --- 4136 RW normal 2048 143872 656384 819200\n" + "----------------------------------------------------------------------------------------------------\n" + " 7 total 56576 12484608 22170240 35799040"; 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