Quickly familiarize yourself with regular expressions in Java and learn how to use them in various use-cases related to string manipulation.

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Regular expressions describe a pattern of characters used for searching a string. They are very useful for parsing information like dates, phone numbers, or zip codes from important text files such as code files, log files, spreadsheets, or documents. 

Below are the most common use cases of regular expressions: 
- Data validation of data fields or values like phone numbers, zip codes, email addresses, etc.
- Information extraction from text files for further processing
- Pattern matching of strings or textual information
- Search and replace operation on texts

This course will teach you how to perform pattern matching with a regular expression using a Java API for these practical use cases.

Tarun Telang

Tarun Telang is a passionate software engineer, leader, architect, author, and active contributor in various online technical forums.

Java Expert & Enterprise Software Architect

Mastering Regular Expressions in Java

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Update the text to search in the `text.txt` file and the regular expression of the `regex.txt` file using the code editor below.
Click the **Run** button to execute the code to see the result of pattern matching.
Here are some of the sample inputs you may try with the program below to strengthen your understanding of Java regex APIs.


Try out various concepts of regular expressions.

Introduction

Java Regex APIs

Building Blocks of Regular Expressions

Course Wrap Up

Regular Expression Tester

Playground for regular expressions