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 = "(department(s)? of |in\\n)(\\w+ ?\\w+[^,]?\\w+[^,]?\\w+[ ]?\\w+[ ]?\\w+)"; final String string = "Virginia Tech Sample:\n" + "A COMPARISON OF THE EFFICIENCY AND EFFECTIVENESS\n" + "OF TWO MODELS FOR DETERMINING THE COST\n" + "OF SPECIAL EDUCATION PROGRAMS\n" + "by\n" + "Kenneth L. Kienas\n" + "Dissertation submitted to the Faculty of the\n" + "Virginia Polytechnic Institute and State University\n" + "in partial fulfillment of the requirements for the degree of\n" + "DOCTOR OF EDUCATION\n" + "in\n" + "Administration and Supervision of Special Education\n" + "APPRQVED:\n" + "Richard G. Salmon, Co-Chairman Phili R. Jones, Co-Chairman\n" + "John A. McLaughlin Shirley A Jones\n" + "Shirley A. Underwood\n" + "May, 1986\n" + "Blacksburg, Virginia\n" + "--------------------------------------------------------\n" + "MIT Sample:\n" + "THE RESPONSE OF CONTINUOUS SYSTEMS\n" + "TO RANDOM NOISE FIELDS\n" + "by \n" + "Richard H. Lyon\n" + "A. B., Evansville College, 1952\n" + "Submitted in Partial Fulfillment of the\n" + "Requirements for the Degree of\n" + "Doctor of Philosophy\n" + "at the\n" + "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" + "June, 1955\n" + "Signature of Author\n" + "department of Physics, May 16, 1955\n" + "Certified by\n" + "Thesis Supervisor\n" + "Accepted by\n" + "Chairman, Departmental Committee on Graduate, Students\n" + "---------------------------------------------------------\n" + "MIT Sample:\n" + "ON THE MECHANICS OF TWIST INSERTION\n" + "by\n" + "ALY H, M, EL-SHIEKH\n" + "B.Sc. University of Alexandria, U.A.R.\n" + "1956\n" + "S.M. Massachusetts Institute of Technology\n" + "1961\n" + "M.E. Massachusetts Institute of Technology\n" + "1964\n" + "Submitted in Partial Fulfillment\n" + "of the Requirements for the\n" + "Degree of Doctor of Science\n" + "at the\n" + "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" + "May 1965\n" + "Signature of the Author\n" + "department of Mechanical Engineering\n" + "Fibers and Polymers Division\n" + "Certified by\n" + "Thesis Supervisor\n" + "Accepted by\n" + "Chairman Departmental Committee on Graduate Students\n" + "------------------------------------------------------------\n" + "MIT Sample:\n" + "HYDRAULIC DAMPER DESIGN\n" + "FOR A KNEE PROSTHESIS\n" + "by\n" + "Eric Hershler Bott\n" + "Submitted in Partial Fulfillment\n" + "of the Requirements for the\n" + "Degree of Bachelor of Science\n" + "at the\n" + "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" + "February, 1975\n" + "Signature of Author\n" + "departments of Mechanical Engineering and\n" + "Physics, February 23, 1975\n" + "Certified by\n" + "Thesis Supervisor\n" + "Accepted by\n" + "Chairman, Departmental Committee on Theses\n" + "MAR 15 1976\n" + "LIBRARIES\n" + "------------------------------------------------------------\n" + "Virginia Tech Sample:\n" + "ASSESSMENT OF A MENTOR PROGRAM\n" + "ON SELF-CONCEPT AND ACHIEVEMENT VARIABLES\n" + "OF MIDDLE SCHOOL UNDERACHIEVERS\n" + "by\n" + "Helene Aiello\n" + "Dissertation submitted to the faculty of the Virginia\n" + "Polytechnic Institute and State University in partial\n" + "fulfillment of the requirements for the degree of\n" + "Doctor of Education\n" + "in\n" + "Administration and Supervision\n" + "Of\n" + "Special Education\n" + "APPROVED:\n" + "Philip R. Jones, Chairman Kenneth Underwood\n" + "Sylvia Auton\n" + "Shirley Jones Ronald McKeen\n" + "February 22, 1988\n" + "Blacksburg, Virginia"; 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