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"
"
g

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 = "^(.*?)/(.*?)?\\s(.*?)\\s(.*?)\\s"; final String string = "libmono-system-xml4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n\n" + "usbmuxd/kali-rolling,now 1.1.0-2+b1 amd64 [installed,automatic]\n\n\n" + "usbutils/kali-rolling,now 1:007-4 amd64 [installed]\n" + "util-linux/kali-rolling,now 2.28-6 amd64 [installed]\n" + "uuid-runtime/kali-rolling,now 2.28-6 amd64 [installed,automatic]\n" + "va-driver-all/kali-rolling,now 1.7.1-2 amd64 [installed,automatic]\n" + "vboot-kernel-utils/kali-rolling,now 0~R52-8350.B-1 amd64 [installed,automatic]\n" + "vboot-utils/kali-rolling,now 0~R52-8350.B-1 amd64 [installed,automatic]\n" + "vdpau-driver-all/kali-rolling,now 1.1.1-3 amd64 [installed,automatic]\n" + "libhttpclient-java/now 4.3.3-1 all [installed,local]\n" + "libhttpcore-java/now 4.3.2-2 all [installed,local]\n" + "libhwloc-dev/now 1.8-1ubuntu1.14.04.1 amd64 [installed,local]\n" + "libhwloc-plugins/now 1.8-1ubuntu1.14.04.1 amd64 [installed,local]\n" + "libhwloc5/now 1.8-1ubuntu1.14.04.1 amd64 [installed,local]\n" + "libhx509-5-heimdal/now 1.6~git20131207+dfsg-1ubuntu1.1 amd64 [installed,local]\n" + "libibverbs-dev/now 1.1.7-1ubuntu1.1 amd64 [installed,local]\n" + "libibverbs1/now 1.1.7-1ubuntu1.1 amd64 [installed,local]\n" + "libice-dev/now 2:1.0.8-2 amd64 [installed,local]\n" + "libice6/now 2:1.0.8-2 amd64 [installed,local]\n" + "libicu-dev/now 52.1-3ubuntu0.4 amd64 [installed,local]\n" + "libicu52/now 52.1-3ubuntu0.4 amd64 [installed,local]\n" + "libid3tag0/now 0.15.1b-10ubuntu1 amd64 [installed,local]\n" + "libidl-common/now 0.8.14-0.2ubuntu4 all [installed,local]\n" + "libidl0/now 0.8.14-0.2ubuntu4 amd64 [installed,local]\n" + "libidn11/now 1.28-1ubuntu2 amd64 [installed,local]\n" + "libieee1284-3/now 0.2.11-12 amd64 [installed,local]\n" + "libmono-system-windows4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-system-xaml4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-system-xml-linq4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-system-xml-serialization4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n\n" + "libmono-system2.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-system4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-tasklets2.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-tasklets4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-wcf3.0a-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-web4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-webbrowser2.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-webbrowser4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-webmatrix-data4.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "libmono-windowsbase3.0-cil/now 3.2.8+dfsg-4ubuntu1.1 all [installed,local]\n" + "nginx/now 1.4.6-1ubuntu3.3 all [installed,local]\n" + "nginx-common/now 1.4.6-1ubuntu3.3 all [installed,local]\n" + "nginx-core/now 1.4.6-1ubuntu3.3 amd64 [installed,local]\n" + "novnc/now 1:0.4+dfsg+1+20131010+gitf68af8af3d-2 all [installed,local]\n" + "ntfs-3g/now 1:2013.1.13AR.1-2ubuntu2 amd64 [installed,local]\n" + "ntpdate/now 1:4.2.6.p5+dfsg-3ubuntu2.14.04.6 amd64 [installed,local]\n" + "ocl-icd-libopencl1/now 2.1.3-4 amd64 [installed,local]\n" + "openjdk-7-doc/now 7u91-2.6.3-0ubuntu0.14.04.1 all [installed,local]\n" + "openjdk-7-jdk/now 7u91-2.6.3-0ubuntu0.14.04.1 amd64 [installed,local]\n" + "openjdk-7-jre/now 7u91-2.6.3-0ubuntu0.14.04.1 amd64 [installed,local]\n" + "openjdk-7-jre-headless/now 7u91-2.6.3-0ubuntu0.14.04.1 amd64 [installed,local]\n" + "openmpi-bin/now 1.6.5-8 amd64 [installed,local]\n" + "openmpi-common/now 1.6.5-8 all [installed,local]\n" + "openssh-client/now 1:6.6p1-2ubuntu2.3 amd64 [installed,local]\n" + "openssl/now 1.0.1f-1ubuntu2.16 amd64 [installed,local]\n" + "parallel/now 20130922-1 all [installed,local]\n" + "parted/now 2.3-19ubuntu1.14.04.1 amd64 [installed,local]\n" + "passwd/now 1:4.1.5.1-1ubuntu9.1 amd64 [installed,local]\n" + "patch/now 2.7.1-4ubuntu2.3 amd64 [installed,local]\n" + "perl/now 5.18.2-2ubuntu1 amd64 [installed,local]\n" + "perl-base/now 5.18.2-2ubuntu1 amd64 [installed,local]\n" + "perl-modules/now 5.18.2-2ubuntu1 all [installed,local]\n" + "pgf/now 2.10-1 all [installed,local]\n" + "php-gettext/now 1.0.11-1 all [installed,local]\n" + "php-pear/now 5.5.9+dfsg-1ubuntu4.14 all [installed,local]\n" + "php5/now 5.5.9+dfsg-1ubuntu4.14 all [installed,local]\n" + "php5-cli/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-common/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-curl/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-dev/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-fpm/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-gd/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-intl/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-json/now 1.3.2-2build1 amd64 [installed,local]\n" + "php5-mcrypt/now 5.4.6-0ubuntu5 amd64 [installed,local]\n" + "php5-mysqlnd/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-pgsql/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-readline/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-sqlite/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-tidy/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-xmlrpc/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "php5-xsl/now 5.5.9+dfsg-1ubuntu4.14 amd64 [installed,local]\n" + "phpmyadmin/now 4:4.0.10-1 all [installed,local]\n" + "phppgadmin/now 5.1-1 all [installed,local]\n" + "pkg-config/now 0.26-1ubuntu4 amd64 [installed,local]\n" + "pkg-php-tools/now 1.11 all [installed,local]\n" + "plymouth/now 0.8.8-0ubuntu17.1 amd64 [installed,local]\n" + "po-debconf/now 1.0.16+nmu2ubuntu1 all [installed,local]\n" + "policykit-1/now 0.105-4ubuntu3.14.04.1 amd64 [installed,local]\n" + "policykit-1-gnome/now 0.105-1ubuntu4 amd64 [installed,local]\n" + "poppler-data/now 0.4.6-4 all [installed,local]\n" + "postgresql-9.3/now 9.3.10-0ubuntu0.14.04 amd64 [installed,local]\n" + "postgresql-client-9.3/now 9.3.10-0ubuntu0.14.04 amd64 [installed,local]\n" + "postgresql-client-common/now 154ubuntu1 all [installed,local]\n" + "postgresql-common/now 154ubuntu1 all [installed,local]\n" + "postgresql-doc/now 9.3+154ubuntu1 all [installed,local]\n" + "postgresql-doc-9.3/now 9.3.10-0ubuntu0.14.04 all [installed,local]\n" + "procps/now 1:3.3.9-1ubuntu2.2 amd64 [installed,local]\n" + "prosper/now 1.00.4+cvs.2007.05.01-4 all [installed,local]\n" + "ps2eps/now 1.68-1build1 amd64 [installed,local]\n" + "psmisc/now 22.20-1ubuntu2 amd64 [installed,local]\n" + "python/now 2.7.5-5ubuntu3 amd64 [installed,local]\n" + "python-amqp/now 1.3.3-1ubuntu1.1 all [installed,local]\n" + "python-amqplib/now 1.0.2-1 all [installed,local]\n" + "python-anyjson/now 0.3.3-1build1 all [installed,local]\n" + "python-apt/now 0.9.3.5ubuntu2 amd64 [installed,local]\n" + "python-apt-common/now 0.9.3.5ubuntu2 all [installed,local]\n" + "python-babel/now 1.3+dfsg.1-2ubuntu2 all [installed,local]\n" + "python-babel-localedata/now 1.3+dfsg.1-2ubuntu2 all [installed,local]\n" + "python-boto/now 2.20.1-2ubuntu2 all [installed,local]\n" + "python-bzrlib/now 2.6.0+bzr6593-1ubuntu1.1 amd64 [installed,local]\n" + "python-cairo/now 1.8.8-1ubuntu5 amd64 [installed,local]\n" + "python-chardet/now 2.0.1-2build2 all [installed,local]\n" + "python-chardet-whl/now 2.2.1-2~ubuntu1 all [installed,local]\n" + "python-cinderclient/now 1:1.0.8-0ubuntu2 all [installed,local]\n" + "python-cliff/now 1.4.5-1ubuntu2 all [installed,local]\n" + "python-cliff-doc/now 1.4.5-1ubuntu2 all [installed,local]\n" + "python-cmd2/now 0.6.7-2fakesync1build1 all [installed,local]\n" + "python-colorama/now 0.2.5-0.1ubuntu2 all [installed,local]\n" + "python-colorama-whl/now 0.2.5-0.1ubuntu2 all [installed,local]\n" + "python-configobj/now 4.7.2+ds-5build1 all [installed,local]\n" + "python-crypto/now 2.6.1-4build1 amd64 [installed,local]\n" + "python-dateutil/now 1.5+dfsg-1ubuntu1 all [installed,local]\n" + "python-dbus/now 1.2.0-2build2 amd64 [installed,local]\n" + "python-dbus-dev/now 1.2.0-2build2 all [installed,local]\n" + "python-decorator/now 3.4.0-2build1 all [installed,local]\n" + "python-dev/now 2.7.5-5ubuntu3 amd64 [installed,local]\n" + "python-distlib/now 0.1.8-1ubuntu1 all [installed,local]\n" + "python-distlib-whl/now 0.1.8-1ubuntu1 all [installed,local]\n" + "python-dns/now 2.3.6-3 all [installed,local]\n" + "python-eventlet/now 0.13.0-1ubuntu2.3 all [installed,local]\n" + "x11proto-xext-dev/now 7.3.0-1 all [installed,local]\n" + "x11vnc/now 0.9.13-1.1 amd64 [installed,local]\n" + "x11vnc-data/now 0.9.13-1.1 all [installed,local]\n" + "xauth/now 1:1.0.7-1ubuntu1 amd64 [installed,local]\n" + "xbitmaps/now 1.1.1-2 all [installed,local]\n" + "xdg-utils/now 1.1.0~rc1-2ubuntu7.1 all [installed,local]\n" + "xfonts-base/now 1:1.0.3 all [installed,local]\n" + "xfonts-encodings/now 1:1.0.4-1ubuntu1 all [installed,local]\n" + "xfonts-terminus/now 4.38-1fakesync1 all [installed,local]\n" + "xfonts-utils/now 1:7.7+1 amd64 [installed,local]\n" + "xkb-data/now 2.10.1-1ubuntu1 all [installed,local]\n" + "xml-core/now 0.13+nmu2 all [installed,local]\n" + "xorg-sgml-doctools/now 1:1.11-1 all [installed,local]\n" + "xserver-common/now 2:1.15.1-0ubuntu2.7 all [installed,local]\n" + "xsltproc/now 1.1.28-2build1 amd64 [installed,local]\n" + "xterm/now 297-1ubuntu1 amd64 [installed,local]\n" + "xtrans-dev/now 1.3.5-1~ubuntu14.04.1 all [installed,local]\n" + "xul-ext-ubufox/now 3.2-0ubuntu0.14.04.1 all [installed,local]\n" + "xvfb/now 2:1.15.1-0ubuntu2.7 amd64 [installed,local]\n" + "xz-utils/now 5.1.1alpha+20120614-2ubuntu2 amd64 [installed,local]\n" + "zip/now 3.0-8 amd64 [installed,local]\n" + "zlib1g/now 1:1.2.8.dfsg-1ubuntu1 amd64 [installed,local]\n" + "zlib1g-dev/now 1:1.2.8.dfsg-1ubuntu1 amd64 [installed,local]\n"; 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