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

/
/

Test String

Substitution

Processing...

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 = "-.*"; final String string = "es-\n" + "af\n" + "af-NA\n" + "af-ZA\n" + "agq\n" + "agq-CM\n" + "ak\n" + "ak-GH\n" + "am\n" + "am-ET\n" + "ar\n" + "ar-001\n" + "ar-AE\n" + "ar-BH\n" + "ar-DJ\n" + "ar-DZ\n" + "ar-EG\n" + "ar-EH\n" + "ar-ER\n" + "ar-IL\n" + "ar-IQ\n" + "ar-JO\n" + "ar-KM\n" + "ar-KW\n" + "ar-LB\n" + "ar-LY\n" + "ar-MA\n" + "ar-MR\n" + "ar-OM\n" + "ar-PS\n" + "ar-QA\n" + "ar-SA\n" + "ar-SD\n" + "ar-SO\n" + "ar-SS\n" + "ar-SY\n" + "ar-TD\n" + "ar-TN\n" + "ar-YE\n" + "as\n" + "as-IN\n" + "asa\n" + "asa-TZ\n" + "ast\n" + "ast-ES\n" + "az\n" + "az-Cyrl\n" + "az-Cyrl-AZ\n" + "az-Latn\n" + "az-Latn-AZ\n" + "bas\n" + "bas-CM\n" + "be\n" + "be-BY\n" + "bem\n" + "bem-ZM\n" + "bez\n" + "bez-TZ\n" + "bg\n" + "bg-BG\n" + "bm\n" + "bm-ML\n" + "bn\n" + "bn-BD\n" + "bn-IN\n" + "bo\n" + "bo-CN\n" + "bo-IN\n" + "br\n" + "br-FR\n" + "brx\n" + "brx-IN\n" + "bs\n" + "bs-Cyrl\n" + "bs-Cyrl-BA\n" + "bs-Latn\n" + "bs-Latn-BA\n" + "ca\n" + "ca-AD\n" + "ca-ES\n" + "ca-FR\n" + "ca-IT\n" + "ccp\n" + "ccp-BD\n" + "ccp-IN\n" + "ce\n" + "ce-RU\n" + "cgg\n" + "cgg-UG\n" + "chr\n" + "chr-US\n" + "ckb\n" + "ckb-IQ\n" + "ckb-IR\n" + "cs\n" + "cs-CZ\n" + "cy\n" + "cy-GB\n" + "da\n" + "da-DK\n" + "da-GL\n" + "dav\n" + "dav-KE\n" + "de\n" + "de-AT\n" + "de-BE\n" + "de-CH\n" + "de-DE\n" + "de-IT\n" + "de-LI\n" + "de-LU\n" + "dje\n" + "dje-NE\n" + "dsb\n" + "dsb-DE\n" + "dua\n" + "dua-CM\n" + "dyo\n" + "dyo-SN\n" + "dz\n" + "dz-BT\n" + "ebu\n" + "ebu-KE\n" + "ee\n" + "ee-GH\n" + "ee-TG\n" + "el\n" + "el-CY\n" + "el-GR\n" + "en\n" + "en-001\n" + "en-150\n" + "en-AG\n" + "en-AI\n" + "en-AS\n" + "en-AT\n" + "en-AU\n" + "en-BB\n" + "en-BE\n" + "en-BI\n" + "en-BM\n" + "en-BS\n" + "en-BW\n" + "en-BZ\n" + "en-CA\n" + "en-CC\n" + "en-CH\n" + "en-CK\n" + "en-CM\n" + "en-CX\n" + "en-CY\n" + "en-DE\n" + "en-DG\n" + "en-DK\n" + "en-DM\n" + "en-ER\n" + "en-FI\n" + "en-FJ\n" + "en-FK\n" + "en-FM\n" + "en-GB\n" + "en-GD\n" + "en-GG\n" + "en-GH\n" + "en-GI\n" + "en-GM\n" + "en-GU\n" + "en-GY\n" + "en-HK\n" + "en-IE\n" + "en-IL\n" + "en-IM\n" + "en-IN\n" + "en-IO\n" + "en-JE\n" + "en-JM\n" + "en-KE\n" + "en-KI\n" + "en-KN\n" + "en-KY\n" + "en-LC\n" + "en-LR\n" + "en-LS\n" + "en-MG\n" + "en-MH\n" + "en-MO\n" + "en-MP\n" + "en-MS\n" + "en-MT\n" + "en-MU\n" + "en-MW\n" + "en-MY\n" + "en-NA\n" + "en-NF\n" + "en-NG\n" + "en-NL\n" + "en-NR\n" + "en-NU\n" + "en-NZ\n" + "en-PG\n" + "en-PH\n" + "en-PK\n" + "en-PN\n" + "en-PR\n" + "en-PW\n" + "en-RW\n" + "en-SB\n" + "en-SC\n" + "en-SD\n" + "en-SE\n" + "en-SG\n" + "en-SH\n" + "en-SI\n" + "en-SL\n" + "en-SS\n" + "en-SX\n" + "en-SZ\n" + "en-TC\n" + "en-TK\n" + "en-TO\n" + "en-TT\n" + "en-TV\n" + "en-TZ\n" + "en-UG\n" + "en-UM\n" + "en-US\n" + "en-US-POSIX\n" + "en-VC\n" + "en-VG\n" + "en-VI\n" + "en-VU\n" + "en-WS\n" + "en-ZA\n" + "en-ZM\n" + "en-ZW\n" + "eo\n" + "es\n" + "es-419\n" + "es-AR\n" + "es-BO\n" + "es-BR\n" + "es-BZ\n" + "es-CL\n" + "es-CO\n" + "es-CR\n" + "es-CU\n" + "es-DO\n" + "es-EA\n" + "es-EC\n" + "es-ES\n" + "es-GQ\n" + "es-GT\n" + "es-HN\n" + "es-IC\n" + "es-MX\n" + "es-NI\n" + "es-PA\n" + "es-PE\n" + "es-PH\n" + "es-PR\n" + "es-PY\n" + "es-SV\n" + "es-US\n" + "es-UY\n" + "es-VE\n" + "et\n" + "et-EE\n" + "eu\n" + "eu-ES\n" + "ewo\n" + "ewo-CM\n" + "fa\n" + "fa-AF\n" + "fa-IR\n" + "ff\n" + "ff-CM\n" + "ff-GN\n" + "ff-MR\n" + "ff-SN\n" + "fi\n" + "fi-FI\n" + "fil\n" + "fil-PH\n" + "fo\n" + "fo-DK\n" + "fo-FO\n" + "fr\n" + "fr-BE\n" + "fr-BF\n" + "fr-BI\n" + "fr-BJ\n" + "fr-BL\n" + "fr-CA\n" + "fr-CD\n" + "fr-CF\n" + "fr-CG\n" + "fr-CH\n" + "fr-CI\n" + "fr-CM\n" + "fr-DJ\n" + "fr-DZ\n" + "fr-FR\n" + "fr-GA\n" + "fr-GF\n" + "fr-GN\n" + "fr-GP\n" + "fr-GQ\n" + "fr-HT\n" + "fr-KM\n" + "fr-LU\n" + "fr-MA\n" + "fr-MC\n" + "fr-MF\n" + "fr-MG\n" + "fr-ML\n" + "fr-MQ\n" + "fr-MR\n" + "fr-MU\n" + "fr-NC\n" + "fr-NE\n" + "fr-PF\n" + "fr-PM\n" + "fr-RE\n" + "fr-RW\n" + "fr-SC\n" + "fr-SN\n" + "fr-SY\n" + "fr-TD\n" + "fr-TG\n" + "fr-TN\n" + "fr-VU\n" + "fr-WF\n" + "fr-YT\n" + "fur\n" + "fur-IT\n" + "fy\n" + "fy-NL\n" + "ga\n" + "ga-IE\n" + "gd\n" + "gd-GB\n" + "gl\n" + "gl-ES\n" + "gsw\n" + "gsw-CH\n" + "gsw-FR\n" + "gsw-LI\n" + "gu\n" + "gu-IN\n" + "guz\n" + "guz-KE\n" + "gv\n" + "gv-IM\n" + "ha\n" + "ha-GH\n" + "ha-NE\n" + "ha-NG\n" + "haw\n" + "haw-US\n" + "he\n" + "he-IL\n" + "hi\n" + "hi-IN\n" + "hr\n" + "hr-BA\n" + "hr-HR\n" + "hsb\n" + "hsb-DE\n" + "hu\n" + "hu-HU\n" + "hy\n" + "hy-AM\n" + "id\n" + "id-ID\n" + "ig\n" + "ig-NG\n" + "ii\n" + "ii-CN\n" + "is\n" + "is-IS\n" + "it\n" + "it-CH\n" + "it-IT\n" + "it-SM\n" + "it-VA\n" + "ja\n" + "ja-JP\n" + "jgo\n" + "jgo-CM\n" + "jmc\n" + "jmc-TZ\n" + "ka\n" + "ka-GE\n" + "kab\n" + "kab-DZ\n" + "kam\n" + "kam-KE\n" + "kde\n" + "kde-TZ\n" + "kea\n" + "kea-CV\n" + "khq\n" + "khq-ML\n" + "ki\n" + "ki-KE\n" + "kk\n" + "kk-KZ\n" + "kkj\n" + "kkj-CM\n" + "kl\n" + "kl-GL\n" + "kln\n" + "kln-KE\n" + "km\n" + "km-KH\n" + "kn\n" + "kn-IN\n" + "ko\n" + "ko-KP\n" + "ko-KR\n" + "kok\n" + "kok-IN\n" + "ks\n" + "ks-IN\n" + "ksb\n" + "ksb-TZ\n" + "ksf\n" + "ksf-CM\n" + "ksh\n" + "ksh-DE\n" + "kw\n" + "kw-GB\n" + "ky\n" + "ky-KG\n" + "lag\n" + "lag-TZ\n" + "lb\n" + "lb-LU\n" + "lg\n" + "lg-UG\n" + "lkt\n" + "lkt-US\n" + "ln\n" + "ln-AO\n" + "ln-CD\n" + "ln-CF\n" + "ln-CG\n" + "lo\n" + "lo-LA\n" + "lrc\n" + "lrc-IQ\n" + "lrc-IR\n" + "lt\n" + "lt-LT\n" + "lu\n" + "lu-CD\n" + "luo\n" + "luo-KE\n" + "luy\n" + "luy-KE\n" + "lv\n" + "lv-LV\n" + "mas\n" + "mas-KE\n" + "mas-TZ\n" + "mer\n" + "mer-KE\n" + "mfe\n" + "mfe-MU\n" + "mg\n" + "mg-MG\n" + "mgh\n" + "mgh-MZ\n" + "mgo\n" + "mgo-CM\n" + "mk\n" + "mk-MK\n" + "ml\n" + "ml-IN\n" + "mn\n" + "mn-MN\n" + "mr\n" + "mr-IN\n" + "ms\n" + "ms-BN\n" + "ms-MY\n" + "ms-SG\n" + "mt\n" + "mt-MT\n" + "mua\n" + "mua-CM\n" + "my\n" + "my-MM\n" + "mzn\n" + "mzn-IR\n" + "naq\n" + "naq-NA\n" + "nb\n" + "nb-NO\n" + "nb-SJ\n" + "nd\n" + "nd-ZW\n" + "nds\n" + "nds-DE\n" + "nds-NL\n" + "ne\n" + "ne-IN\n" + "ne-NP\n" + "nl\n" + "nl-AW\n" + "nl-BE\n" + "nl-BQ\n" + "nl-CW\n" + "nl-NL\n" + "nl-SR\n" + "nl-SX\n" + "nmg\n" + "nmg-CM\n" + "nn\n" + "nn-NO\n" + "nnh\n" + "nnh-CM\n" + "nus\n" + "nus-SS\n" + "nyn\n" + "nyn-UG\n" + "om\n" + "om-ET\n" + "om-KE\n" + "or\n" + "or-IN\n" + "os\n" + "os-GE\n" + "os-RU\n" + "pa\n" + "pa-Arab\n" + "pa-Arab-PK\n" + "pa-Guru\n" + "pa-Guru-IN\n" + "pl\n" + "pl-PL\n" + "ps\n" + "ps-AF\n" + "pt\n" + "pt-AO\n" + "pt-BR\n" + "pt-CH\n" + "pt-CV\n" + "pt-GQ\n" + "pt-GW\n" + "pt-LU\n" + "pt-MO\n" + "pt-MZ\n" + "pt-PT\n" + "pt-ST\n" + "pt-TL\n" + "qu\n" + "qu-BO\n" + "qu-EC\n" + "qu-PE\n" + "rm\n" + "rm-CH\n" + "rn\n" + "rn-BI\n" + "ro\n" + "ro-MD\n" + "ro-RO\n" + "rof\n" + "rof-TZ\n" + "ru\n" + "ru-BY\n" + "ru-KG\n" + "ru-KZ\n" + "ru-MD\n" + "ru-RU\n" + "ru-UA\n" + "rw\n" + "rw-RW\n" + "rwk\n" + "rwk-TZ\n" + "sah\n" + "sah-RU\n" + "saq\n" + "saq-KE\n" + "sbp\n" + "sbp-TZ\n" + "se\n" + "se-FI\n" + "se-NO\n" + "se-SE\n" + "seh\n" + "seh-MZ\n" + "ses\n" + "ses-ML\n" + "sg\n" + "sg-CF\n" + "shi\n" + "shi-Latn\n" + "shi-Latn-MA\n" + "shi-Tfng\n" + "shi-Tfng-MA\n" + "si\n" + "si-LK\n" + "sk\n" + "sk-SK\n" + "sl\n" + "sl-SI\n" + "smn\n" + "smn-FI\n" + "sn\n" + "sn-ZW\n" + "so\n" + "so-DJ\n" + "so-ET\n" + "so-KE\n" + "so-SO\n" + "sq\n" + "sq-AL\n" + "sq-MK\n" + "sq-XK\n" + "sr\n" + "sr-Cyrl\n" + "sr-Cyrl-BA\n" + "sr-Cyrl-ME\n" + "sr-Cyrl-RS\n" + "sr-Cyrl-XK\n" + "sr-Latn\n" + "sr-Latn-BA\n" + "sr-Latn-ME\n" + "sr-Latn-RS\n" + "sr-Latn-XK\n" + "sv\n" + "sv-AX\n" + "sv-FI\n" + "sv-SE\n" + "sw\n" + "sw-CD\n" + "sw-KE\n" + "sw-TZ\n" + "sw-UG\n" + "ta\n" + "ta-IN\n" + "ta-LK\n" + "ta-MY\n" + "ta-SG\n" + "te\n" + "te-IN\n" + "teo\n" + "teo-KE\n" + "teo-UG\n" + "tg\n" + "tg-TJ\n" + "th\n" + "th-TH\n" + "ti\n" + "ti-ER\n" + "ti-ET\n" + "to\n" + "to-TO\n" + "tr\n" + "tr-CY\n" + "tr-TR\n" + "tt\n" + "tt-RU\n" + "twq\n" + "twq-NE\n" + "tzm\n" + "tzm-MA\n" + "ug\n" + "ug-CN\n" + "uk\n" + "uk-UA\n" + "ur\n" + "ur-IN\n" + "ur-PK\n" + "uz\n" + "uz-Arab\n" + "uz-Arab-AF\n" + "uz-Cyrl\n" + "uz-Cyrl-UZ\n" + "uz-Latn\n" + "uz-Latn-UZ\n" + "vai\n" + "vai-Latn\n" + "vai-Latn-LR\n" + "vai-Vaii\n" + "vai-Vaii-LR\n" + "vi\n" + "vi-VN\n" + "vun\n" + "vun-TZ\n" + "wae\n" + "wae-CH\n" + "wo\n" + "wo-SN\n" + "xog\n" + "xog-UG\n" + "yav\n" + "yav-CM\n" + "yi\n" + "yi-001\n" + "yo\n" + "yo-BJ\n" + "yo-NG\n" + "yue\n" + "yue-Hans\n" + "yue-Hans-CN\n" + "yue-Hant\n" + "yue-Hant-HK\n" + "zgh\n" + "zgh-MA\n" + "zh\n" + "zh-Hans\n" + "zh-Hans-CN\n" + "zh-Hans-HK\n" + "zh-Hans-MO\n" + "zh-Hans-SG\n" + "zh-Hant\n" + "zh-Hant-HK\n" + "zh-Hant-MO\n" + "zh-Hant-TW\n" + "zu\n" + "zu-ZA"; final String subst = ""; final Pattern pattern = Pattern.compile(regex); final Matcher matcher = pattern.matcher(string); // The substituted value will be contained in the result variable final String result = matcher.replaceFirst(subst); System.out.println("Substitution result: " + result); } }

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