Drools JBoss Rules 5.X Developer’s Guide

Define and execute your business rules with Drools

Overview

• Learn the power of Drools as a platform for writing your business rules
• Learn the power of Drools as a platform for writing your busiIntegrate Drools into your Java business application using the Spring frameworkness rules
• Through real-world examples and solutions, you will be taken from novice to expert

In Detail

Writing business rules has always been a challenging task. Business rules tend to change often leading to a maintenance nightmare. This book shows you various ways to code your business rules using Drools, the open source Business Rules Management System.

Drools JBoss Rules 5.X Developer’s Guide shows various features of the Drools platform by walking the reader through several real-world examples. Each chapter elaborates on different aspects of the Drools platform. The reader will also learn about the inner workings of Drools and its implementation of the Rete algorithm.

The book starts with explaining rule basics, then builds on this information by going through various areas like human readable rules, rules for validation, and stateful rules, using examples from the banking domain. A loan approval process example shows the use of the jBPM module. Parts of a banking fraud detection system are implemented with the Drools Fusion module which is the complex event processing part of Drools. Finally, more technical details are shown detailing the inner workings of Drools, the implementation of the ReteOO algorithm, indexing, node sharing, and partitioning.

What you will learn from this book

• Quickly get started writing your first rules
• Produce decision tables
• Write a domain-specific language to make rules more understandable
• Create a stateful service
• Harness the power of flows through process services
• Fit it all together in a sample web application that uses layered architecture, transactions, Spring, and Hibernate
• Properly test your applications with Guvnor

Approach

The chapters in the book present real-life examples, usually starting with an introduction to the problem, and a discussion of the possible solution. Then the solution is implemented in a step by step fashion implementing several rules.

Who this book is written for

The book is for Java developers who want to create rule-based business logic using the Drools platform.

Table of Contents

Chapter 1: Programming Declaratively
Chapter 2: Writing Basic Rules
Chapter 3: Validating
Chapter 4: Transforming Data
Chapter 5: Creating Human-readable Rules
Chapter 6: Working with Stateful Session
Chapter 7: Complex Event Processing
Chapter 8: Defining Processes with jBPM
Chapter 9: Building a Sample Application
Chapter 10: Testing
Chapter 11: Integrating
Chapter 12: Learning about Performance

Appendix A: Setting Up the Development Environment
Appendix B: Creating Custom Operators
Appendix C: Dependencies of Sample Application