dehasi/ppp-of-ddd

Java sample code for PPP of DDD book

Principles, Practices and Patterns of Domain-Driven Design

This repository is Java adaptation of sample code for the book Principles, Practices and Patterns of Domain-Driven Design. The original code is written in C#. Samples use various frameworks and technologies. These frameworks were replaced with the most close Java equivalents. Samples in some chapters are complete applications. For such chapters, I added additional readmes. I described replacements, problems, and screenshots of running apps.

Table of Contents

• Replacements
• Chapters with Additional Readme
  • Chapter 12
  • Chapter 13
  • Chapter 15
  • Chapter 18
  • Chapter 21
  • Chapter 22
  • Chapter 23
  • Chapter 25
  • Chapter 26
• Contributing

Replacements

Most technologes are replaced with equivalents that are popular in the Java world.

Table 1. technologies

Original	Equivalent	Comment
ASP.NET	Spring Thymeleaf	See README in CH12, CH23
NServiceBus	RabbitMQ, ApplicationEventPublisher	See README in CH12 and CH18
Mass Transit	Kafka	See README in CH12
Syndication	rometools	See README in CH13
NHibernate	Hibernate	I skipped fluent-hibernate, see README in CH15, CH21
StringExtensions	TheString	Java doesn’t support this feature, I used a ZeLiba.
SQL Server Express	MySQL, H2, SQLite	see README CH21
StructureMap	I made DI manually	see README CH21
EntityFramework	JOOQ with SQLite	see README CH21
Dapper Micro ORM	JDBI with SQLite	see README CH21

Besides replacement of technologies, there is some language "sugar" to keep code more aligned to the book examples.

Table 2. replacements

Original	Equivalent	Comment
GUID	UUID	As it’s just an example, for this project, there is no difference
decimal	BigDecimal with TheComparable	ZeLiba for fluent comparison, as Java doesn’t support > or < for BigDecimal.
NotImplementedException	own NotImplementedException	see java-replacements
ApplicationException	own ApplicationException	see java-replacements
ArgumentNullException	NullPointerException	usually inside Objects.requireNonNull
InvalidOperationException	own InvalidOperationException	see java-replacements
IEnumerable	Arrays or List<>

Chapters with Additional Readme

The chapters below contain a detailed description of what I did, which replacements I used and why, which problems I’d faced and how I solved or worked around them.

Chapter 12

It’s a big chapter, and it requires a separate readme. See ch12/README.adoc for details.

Chapter 13

It’s a big chapter, and it requires a separate readme. See ch13/README.adoc for details.

Chapter 15

This chapter required a bit of work with Hibernate. See ch15/README.adoc for details.

Chapter 18

This chapter required a bit of work with "Static" DomainEvents. See ch18/README.adoc for details.

Chapter 21

This chapter required a bit of work with ORMs and databases. See ch21/README.adoc for details.

Chapter 22

This chapter required a bit of work with event sourcing. See ch22/README.adoc for details.

Chapter 23

This chapter required a bit of work with ThymeLeaf. See ch23/README.adoc for details.

Chapter 25

This chapter required a bit of work with ThymeLeaf and Commands Handlers. See ch25/README.adoc for details.

Chapter 26

This chapter required a bit of work with EventStoreDB. See ch26/README.adoc for details.

Contributing

Improvements are welcome! Feel free to create issues or pull requests. Fixing mistyping in readmes is also welcome!

Each readme has a ToDon’t list. It’s a list of potential improvements, but I won’t have time for them. Feel free to check them.