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 single character of: a, b, c or d
    [[ab][cd]]
  • 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]
  • Character class intersection
    [\w&&[^\d]]
  • 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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = "^(?<type>(?:ci-|cloud-)?[^-]+)[_-](?<version>\\d+\\.\\d+\\.\\d+)(?<alpha>[-+]alpha)?(?:-(?<date>\\d{8}))?[-+](?:(?<build>\\d+).(?<builddate>\\d{8}))?(?:[.-]?(?<sha>[A-Fa-f0-9]+(?:[.-]\\d+)?))?(?:\\.(?<arch>.+))?\\.(?<fmt>.{3})"; final String string = "cloud-csm-6.4.13-20210927-89fa91ca.lnx.x86_64.zip\n" + "cams-7.2.4+4.20211216.zip\n" + "cams-7.2.4-alpha+4.20211216.zip\n" + "cca-6.4.23+753.20211216.193a0386-1.noarch.rpm\n" + "cca-6.4.23+alpha+753.20211216.193a0386-1.noarch.rpm\n" + "cca-6.4.23-alpha+753.20211216.193a0386.zip\n" + "cca_6.4.23+753.20211216.193a0386-1_all.deb\n" + "ci-j2ee-6.4.23+790.20211216.193a0386.zip\n" + "ci-j2ee-6.4.23-alpha+790.20211216.193a0386.zip\n" + "ci-server-6.4.23+790.20211216.193a0386.zip\n" + "ci-server-6.4.23-alpha+790.20211216.193a0386.zip\n" + "cloud-ci-7.1.15+90.20210119.46eef7d3-1.noarch.rpm\n" + "cloud-ci-7.2.4+247.20211216.eba3915b.noarch.zip\n" + "cloud-ci-7.2.4+alpha+247.20211216.eba3915b-1.noarch.RPM\n" + "cloud-ci-7.2.4-alpha+247.20211216.eba3915b.noarch.zip\n" + "cloud-cm-7.2.4+246.20211216.eba3915b-1.noarch.rpm\n" + "cloud-cm-7.2.4+246.20211216.eba3915b.noarch.zip\n" + "cloud-cm-7.2.4+alpha+246.20211216.eba3915b-1.noarch.rpm\n" + "cloud-cm-7.2.4-alpha+246.20211216.eba3915b.noarch.zip\n" + "cloud-csd-7.2.4+241.20211216.eba3915b-1.x86_64.rpm\n" + "cloud-csd-7.2.4+241.20211216.eba3915b.1-sym-x86_64.rpm\n" + "cloud-csd-7.2.4+241.20211216.eba3915b.lnx.x86_64.zip\n" + "cloud-csd-7.2.4+241.20211216.eba3915b.sym.lnx.x86_64.zip\n" + "cloud-csd-7.2.4+alpha+241.20211216.eba3915b-1.x86_64.rpm\n" + "cloud-csd-7.2.4+alpha+241.20211216.eba3915b.1-sym-x86_64.rpm\n" + "cloud-csd-7.2.4-alpha+241.20211216.eba3915b.lnx.x86_64.zip\n" + "cloud-csd-7.2.4-alpha+241.20211216.eba3915b.sym.lnx.x86_64.zip\n" + "cloud-csm-6.4.13-20210927-89fa91ca.lnx.x86_64.zip\n" + "cloud-csm-6.4.13-20210927-89fa91ca.win.x86.zip\n" + "cloud-cst-7.2.4+241.20211216.eba3915b-1.x86_64.rpm\n" + "cloud-cst-7.2.4+241.20211216.eba3915b.1-sym-x86_64.rpm\n" + "cloud-cst-7.2.4+241.20211216.eba3915b.lnx.x86_64.zip\n" + "cloud-cst-7.2.4+241.20211216.eba3915b.sym.lnx.x86_64.zip\n" + "cloud-cst-7.2.4+alpha+241.20211216.eba3915b-1.x86_64.rpm\n" + "cloud-cst-7.2.4+alpha+241.20211216.eba3915b.1-sym-x86_64.rpm\n" + "cloud-cst-7.2.4-alpha+241.20211216.eba3915b.lnx.x86_64.zip\n" + "cloud-cst-7.2.4-alpha+241.20211216.eba3915b.sym.lnx.x86_64.zip\n" + "cloud-parts-7.2.4-20211216.zip\n" + "cloud-parts-7.2.4-alpha-20211216.zip\n" + "cloud-xds-6.4.6-20211101-4b76a168.lnx.x86.zip\n" + "cloud-xds-6.4.6-20211101-4b76a168.win.x86.zip\n" + "cm-6.4.23+798.20211216.193a0386-1.noarch.rpm\n" + "cm-6.4.23+alpha+798.20211216.193a0386-1.noarch.rpm\n" + "cm-6.4.23-alpha+798.20211216.193a0386.zip\n" + "cm_6.4.23+798.20211216.193a0386-1_all.deb\n" + "cm_6.4.23+alpha+798.20211216.193a0386-1_all.deb\n" + "csm-6.4.13-20210927-89fa91ca.lnx.x86_64.tar\n" + "csm-6.4.13-20210927-89fa91ca.win.x86.zip\n" + "dbconfig-7.2.4+231.20211216.eba3915b.zip\n" + "dbconfig-7.2.4-alpha+231.20211216.eba3915b.zip\n" + "xds-6.4.6-20211101-4b76a168.lnx.x86.tar\n" + "xds-6.4.6-20211101-4b76a168.win.x86.zip"; 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