Java 9 Regular Expressions

Key Features

Discover regular expressions and how they work
Implement regular expressions with Java to your code base
Learn to use regular expressions in emails, URLs, paths, and IP addresses

Book Description

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.

What you will learn

Understand the semantics, rules, and core concepts of writing Java code involving regular expressions
Learn about the java.util.Regex package using the Pattern class, Matcher class, code snippets, and more
Match and capture text in regex and use back-references to the captured groups
Explore Regex using Java String methods and regex capabilities in the Java Scanner API
Use zero-width assertions and lookarounds in regex
Test and optimize a poorly performing regex and various other performance tips

About the Author

Anubhava Srivastava has more than 22 years of professional experience in architecture, design, and software development. He specializes mainly in the J2EE technology stack, web technologies, CICD, test-driven development, and AWS cloud-based development.

He is an active contributor to the Stack Overflow community. He currently stands in the top 35 users in terms of reputations out of the 7.5 million Stack Overflow users. He is passionate about regular expressions and is always willing to sharpen his regex skills further. He has answered close to 10,000 regex questions on Stack Overflow.

He has authored and released a test-driven framework, called GenericFixture, for FitNesse as an open source software.

You can follow him on Twitter at @anubhava.

Table of Contents

Getting Started with Regular Expressions
Understanding the Core Constructs of Java Regular Expressions
Working with Groups, Capturing, and References
Regular Expression Programming Using Java String and Scanner APIs
Introduction to Java Regular Expression APIs - Pattern and Matcher Classes
Exploring Zero-width Assertions, Lookarounds, and Atomic Groups
Understanding the Union, Intersection, and Subtraction of Character Classes
Regular Expression Pitfalls, Optimization, and Performance Improvements