Book Image

Java 9 Regular Expressions

By : Anubhava Srivastava
Book Image

Java 9 Regular Expressions

By: Anubhava Srivastava

Overview of this book

Regular expressions are a powerful tool in the programmer's toolbox and allow pattern matching. They are also used for manipulating text and data. This book will provide you with the know-how (and practical examples) to solve real-world problems using regex in Java. You will begin by discovering what regular expressions are and how they work with Java. This easy-to-follow guide is a great place from which to familiarize yourself with the core concepts of regular expressions and to master its implementation with the features of Java 9. You will learn how to match, extract, and transform text by matching specific words, characters, and patterns. You will learn when and where to apply the methods for finding patterns in digits, letters, Unicode characters, and string literals. Going forward, you will learn to use zero-length assertions and lookarounds, parsing the source code, and processing the log files. Finally, you will master tips, tricks, and best practices in regex with Java.
Table of Contents (15 chapters)
Title page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface
Free Chapter
1
Getting Started with Regular Expressions

How to test and benchmark your regular expression performance


There are several free online regular expression tools available that tell you the number of steps to match a regex pattern against a given set of inputs and also provide you valuable debug info. You should also write your unit test cases. Here is a list of some online tools that can be used:

In addition to these tools, you can yourself write your own comprehensive unit test cases using JUnit in your favorite Java IDE and check the timings and other matching information.

Here is an example of JUnit code using the RegExMatchers library:

package example.regex...