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

/
/
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 = "^\\d*\\n(.*)\\n([^\\d].*|)"; final String string = "1\n" + "Mecca (مكة)\n" + "Trading hub and sanctuary in pre-Islamic Arabia; holy city to Muslims; current capital of Makkah Province, Saudi Arabia\n" + "2\n" + "Medina (المدينة)\n" + "Political seat of Muhammad, and first capital of the Rashidun Caliphate; current capital of Al Madinah Province, Saudi Arabia\n" + "3\n" + "Damascus (دمشق)\n" + "Capital of the Umayyad dynasty; current capital of Syria\n" + "4\n" + "Baghdad (بغداد)\n" + "Second capital of the Abbasid dynasty, and actual seat of Harun al-Rashid; current capital of Iraq\n" + "5\n" + "Najran (نجران)\n" + "Christian center in 5th-7th century Arabia; current capital of Najran Province, Saudi Arabia \n" + "6\n" + "Kufah (الكوفة)\n" + "Second capital of the Rashidun Caliphate under Ali's rule; first capital of the Abbasid dynasty; city in modern-day Iraq\n" + "7\n" + "Basra (البصرة)\n" + "City in Iraq\n" + "8\n" + "Khurasan (خراسان)\n" + "Region corresponding to modern Afghanistan and northeast Iran\n" + "9\n" + "Anjar (عنجر)\n" + "City in Lebanon\n" + "10\n" + "Fustat (الفسطاط)\n" + "Old city of Cairo\n" + "11\n" + "Aden (عدن)\n" + "City in Yemen\n" + "12\n" + "Yamama (اليمامة)\n" + "Modern Najd region of Saudi Arabia\n" + "13\n" + "Muscat (مسقط)\n" + "Capital of Oman\n" + "14\n" + "Mansura (المنصورة)\n" + "City in Egypt\n" + "15\n" + "Bukhara (بخارى)\n" + "Modern day Buxoro, capital of Buxoro Province, Uzbekistan\n" + "16\n" + "Fez (فاس)\n" + "Shared with Morocco, not buildable if they are in the game\n" + "17\n" + "Shiraz (شيراز)\n" + "Capital of Fārs Province, Iran\n" + "18\n" + "Merw (ميرف)\n" + "Modern day Mary; capital of Mary Province, Turkmenistan\n" + "19\n" + "Balkh (بلخ)\n" + "City in Afghanistan\n" + "20\n" + "Mosul (الموصل)\n" + "City in Iraq\n" + "21\n" + "Aydab (؟؟؟؟؟)\n" + "22\n" + "Bayt Ras (؟؟؟؟؟؟)\n" + "23\n" + "Suhar (صحار)\n" + "City in Oman\n" + "24\n" + "Taif (طائف)\n" + "City in Saudi Arabia\n" + "25\n" + "Hama (حماة)\n" + "Capital of Hamāh Governorate, Syria\n" + "26\n" + "Tabuk (تبوك)\n" + "Capital of Tabūk Province, Saudi Arabia\n" + "27\n" + "Sana'a (صنعاء)\n" + "Capital of Yemen\n" + "28\n" + "Shihr (الشحر)\n" + "City in Yemen\n" + "29\n" + "Tripoli (طرابلس)\n" + "Capital of Libya\n" + "30\n" + "Tunis (تونس)\n" + "Capital of Tunisia\n" + "31\n" + "Kairouan (القيروان)\n" + "City in Tunisia\n" + "32\n" + "Algiers (الجزائر)\n" + "Capital of Algeria\n" + "33\n" + "Oran (وهران)\n" + "City in Algeria\n" + "34\n" + "Tangier (طنجة)\n" + "Shared with Morocco, not buildable if they are in the game\n" + "35\n" + "Casablanca (الدار البيضاء)\n" + "Shared with Morocco, not buildable if they are in the game\n" + "36\n" + "Marrakech (مراكش)\n" + "Shared with Morocco, not buildable if they are in the game"; 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