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

/
/
gmx

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 = "^(?i)\\s*(\"?)(?>(?<colname>\\w+))\\1\n" + " \\s+\n" + " (?:(?<type>\\b\\w+\\b)\\s*(?:\\((?<typepars>(?:\\w|\\s|\\,|\\*)+)\\))?)\n" + " \\s*\n" + " (\\bdefault\\s+(?<defaultval>(\\(?)(null|\\w+|\\'\\s\\')+?\\)?))?\n" + " \\s*\n" + " (?:(?:\\bconstraint\\s+(\")(?<constraint_name>\\w+)\\9\\s+)?(?<nullable>not\\s+null\\b)\\s+enable)?\n" + " (,?)(\\s*)(?-i)$"; final String string = "\"a1\" NUMBER(10,0) CONSTRAINT \"ca1\" NOT NULL ENABLE, \n" + " \"a2\" NUMBER(10,0) CONSTRAINT \"ca2\" NOT NULL ENABLE, \n" + " \"a3\" NUMBER(14,0) DEFAULT 0 CONSTRAINT \"ca3\" NOT NULL ENABLE, \n" + " \"a4\" VARCHAR2(60 CHAR), \n" + " \"a5\" NUMBER(10,0), \n" + " \"a6\" NUMBER(10,0) DEFAULT 0 CONSTRAINT \"ca6\" NOT NULL ENABLE, \n" + " \"a7\" NUMBER(5,0) DEFAULT 0 CONSTRAINT \"ca7\" NOT NULL ENABLE, \n" + " \"a8\" NUMBER(5,0) DEFAULT 0 CONSTRAINT \"ca8\" NOT NULL ENABLE, \n" + " \"abc\" TIMESTAMP (6) DEFAULT SYSDATE NOT NULL ENABLE, \n" + " \"def\" CHAR(3 CHAR) NOT NULL ENABLE, \n" + " \"ghi\" CHAR(3 CHAR) NOT NULL ENABLE, \n" + " \"XML\" CLOB NOT NULL ENABLE, \n" + " \"jkl\" CHAR(6 CHAR), \n" + " \"mno\" NUMBER(*,0), \n" + " \"pqr\" NUMBER(*,0) DEFAULT (0) NOT NULL ENABLE, "; final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE | Pattern.COMMENTS); 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