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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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 = ".+(?=\\sProject #)"; final String string = "Return to Contents\n\n" + "Street Improvements\n\n" + "Ocotillo Road – Greenfield to Higley Project #: ST0540\n\n" + "Project Description:\n" + "Design and construction of Ocotillo Road from approximately ¼ mile east of Greenfield Road to Higley Road to\n" + "minor arterial standards. The project includes crossings over the Queen Creek Wash, East Maricopa Floodway,\n" + "Roosevelt Water Conservation District Canal and Chandler Heights Basin. The project includes the relocation of\n" + "69kV power lines and access into the proposed Gilbert Regional Park.\n\n" + "Project Information:\n" + "• Costs shown in prior years are for completion of an alignment study in FY 2009\n" + "to coordinate the alignment with Flood Control District projects\n" + "• Maintenance costs will be determined once final design is completed. Ongoing\n" + "maintenance costs will be a consideration in selection of the project design\n" + "• Project is necessary for growth/development and therefore is eligible for\n" + "System Development Fee funding\n\n" + "Financial Information:\n" + "Expenses: (1,000s) Total Prior FY 2021 FY 2022 FY 2023 FY 2024 FY 2025 Years 6- Beyond\n" + "Years 10 10 Yrs\n" + "Professional Services $ 6,104 299 5,805 - - - - - -\n" + "Construction Mgmt $ 4,316 33 4,283 - - - - - -\n" + "Land/ROW $ 2,325 - 2,325 - - - - - -\n" + "Construction $ 53,774 - - 53,774 - - - - -\n" + "Equipment & Furniture $ - - - - - - - - -\n\n" + "Total Expenses $ 66,519 $ 332 $ 12,413 $ 53,774 $ - $ - $ - $ - $ -\n\n" + "Sources: (1,000s)\n\n" + "2007 GO Bonds 08 $ 246 246 - - - - - - -\n" + "2022 Potential Street Bond $ 50,701 - - 50,701 - - - - -\n" + "CIP O/S Revolving Fund $ 375 86 289 - - - - - -\n" + "Roads SDF $ 15,197 - 12,124 3,073 - - - - -\n\n" + "Total Sources $ 66,519 $ 332 $ 12,413 $ 53,774 $ - $ - $ - $ - $ -\n\n" + "Operation and Maintenance Impact: (1,000s)\n\n" + "Personnel - - - - -\n" + "Contractual Services - - - - -\n" + "Supplies - - - - -\n" + "Utilities - - - - -\n" + "Insurance - - - - -\n\n" + "Total O&M Impact $ - $ - $ - $ - $ -\n\n" + "Total Revenue $ - $ - $ - $ - $ -\n\n" + "49"; 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