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

/
/
g

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 = "([a-zA-Z,.:;\\s]+)"; final String string = " Cross, Kumaraswamy Layout Bangalore-560078, India \n" + "Date of Birth: 17 January, 1990 Phone: 9916970905 Email: neelmani.nm@gmail.com \n" + " \n" + "Seeking Data Scientist position \n" + "SYNOPSIS: * \n" + " Proficient in programming, statistical analysis, data visualization in R \n" + " On-time delivery with utmost quality \n" + " Data driven solution for business problems \n" + " Remarkable ability to identify, extract, analyze and disseminate statistical analysis \n" + " Highly motivated to learn and grow in Data Science \n" + " \n" + "PROFESSIONAL EXPERIENCE \n" + " \n" + "ORGANIZATION: Flutura Data \n" + "Science and Analytics \n" + " \n" + "Category: Service provider \n" + "Domain: Energy, Online Search \n" + "Designation: Data Scientist (Apr 2015 – July 2015) \n" + " \n" + "Role and Responsibilities \n" + " Understanding project requirements \n" + " Getting and Cleaning the data from different data sources using R and Python \n" + " Exploratory data analysis, Data Mining, Data Modelling \n" + " Insight generation and recommendations \n" + " \n" + "ORGANIZATION: Trianz Holding \n" + "Pvt. Ltd. \n" + " \n" + "Category: Service provider \n" + "Domain: e-Governance, Security and \n" + "Protection, Maritime Logistics \n" + "Designation: Software Engineer (July 2012 – Sep 2014) \n" + " \n" + "Role and Responsibilities \n" + " Understanding and gathering project requirements \n" + " Gathering information regarding different data sources \n" + " Identification and conversion of data for analytical modeling \n" + " Report development on the insights of the data \n" + " Migration of data between different data storage location \n" + " Insight generation and recommendations \n" + " \n" + " \n" + "EDUCATION \n" + " \n" + "Dayananda Sagar College of Engineering, \n" + "Bangalore \n" + "Bachelor of Engineering (B.E), June 2012 \n" + "Major: Telecom., 64.5% \n" + "CBSE – 2006 (XIIth ) – Guru Govind Singh Public School, Bokaro - 73% \n" + "CBSE – 2004 (Xth ) – Jeevan Deep Public School, Nawada - 84% \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " \n" + " SKILLS \n" + " \n" + "Proficient in R, SQL, MS EXCEL, Pentaho and analytical techniques like linear regression, logistic regression, Hypothesis \n" + "testing, chi square test, ANOVA etc \n" + "Exposer of Python, Qlikview, Tableau \n" + " \n" + " \n" + " CERTIFICATIONS \n" + " \n" + " Foundation of Data Science, University of Texas (MOOC Programme) \n" + " The Data Scientist’s Toolbox, Jhons Hopkins University (Coursera verified certificate) \n" + " R Programming, Jhons Hopkins University (Coursera verified certificate) \n" + " Getting and Cleaning Data, Jhons Hopkins University (Coursera verified certificate) \n" + " Exploratory Data Analysis, Jhons Hopkins University (Coursera verified certificate) \n" + " Reproducibility of Research, Jhons Hopkins University (Coursera verified certificate) \n" + " Statistical Inference, Jhons Hopkins University (Coursera verified certificate) \n" + " Certification in ITIL Foundation \n" + " \n" + "PROJECTS \n" + " \n" + "Online Search:- \n" + "Reports and dashboard for analyzing the user preference for using online search engine. Reports have to be generated for regular \n" + "time interval using R to analyze the trend. \n" + "Energy:- \n" + "Analyzed churn problem by using data from different data sources and logistic regression. A statistical model for predicting the \n" + "future churn. Analyzed the problem and the retail energy domain in US which helped to come up with a statistical model. \n" + "Marine Industry:- \n" + "Gather data from different data sources involving different information regarding the vessel. On top of which analytical insights \n" + "for the vessel performance. \n" + " \n" + "Security and Protection:- \n" + "Fortune 500 company in the securities and protection. Using different data sources centralized reporting system has been \n" + "developed \n" + " \n" + "e-Governance:- \n" + "e-Govenance is a data migration project which is meant to migrate the different department data of the government to a common \n" + "data model. \n"; final Pattern pattern = Pattern.compile(regex); 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