In this chapter, you learned how to capture and reference substrings from an input text using regular expressions. Using non-capturing groups, we discussed how to optimize our regex patterns. We discussed the various types of groups available in Java regular expressions, the numbering of captured groups, and named groups. You also learned how to use back reference and forward reference of the capturing groups using numbered and named references. In the next chapter, you will get to writing code in Java to evaluate regular expressions. You will also be introduced to Java regular expressions using the Java String API, and then, we will move on to regex capabilities in the Java Scanner API.
Java 9 Regular Expressions
By :
Java 9 Regular Expressions
By:
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
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
Customer Reviews