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[1/2] isis git commit: ISIS-1133: further updates to the intro doc.
Repository: isis
Updated Branches:
refs/heads/ISIS-1133 61b99ff02 -> 3f14ded5a
ISIS-1133: further updates to the intro doc.
Project: http://git-wip-us.apache.org/repos/asf/isis/repo
Commit: http://git-wip-us.apache.org/repos/asf/isis/commit/143f190f
Tree: http://git-wip-us.apache.org/repos/asf/isis/tree/143f190f
Diff: http://git-wip-us.apache.org/repos/asf/isis/diff/143f190f
Branch: refs/heads/ISIS-1133
Commit: 143f190fcff3c4ca4d83aeefa8e40bb35b3310ef
Parents: 61b99ff
Author: Dan Haywood <da...@haywood-associates.co.uk>
Authored: Wed Apr 29 09:14:00 2015 +0100
Committer: Dan Haywood <da...@haywood-associates.co.uk>
Committed: Wed Apr 29 09:14:00 2015 +0100
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.../_user-guide_core-concepts_principles.adoc | 244 ++++++++++++++++++-
1 file changed, 239 insertions(+), 5 deletions(-)
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diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
index 4271abb..014a0b9 100644
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
@@ -5,16 +5,250 @@
IMPORTANT: TODO
-## Domain-Driven Design
+== Domain-Driven Design
+
+There's no doubt that we developers love the challenge of understanding
+and deploying complex technologies. But understanding the nuances and
+subtleties of the business domain itself is just as great a challenge,
+perhaps more so. If we devoted our efforts to understanding and addressing
+those subtleties, we could build better, cleaner, and more maintainable
+software that did a better job for our stakeholders. And there's no doubt
+that our stakeholders would thank us for it.
+
+A couple of years back Eric Evans wrote his book Domain-Driven Design</bookname>, which is well on its way to
+becoming a seminal work. In fact, most if not all of the ideas in Evans'
+book have been expressed before, but what he did was pull those ideas
+together to show how predominantly object-oriented techniques can be used
+to develop rich, deep, insightful, and ultimately useful business
+applications.
+
+So, let's start off by reviewing the essential ideas of DDD.
+
+=== The Essentials of DDD
+
+There are two central ideas at the heart of domain-driven design.
+
+* The ubiquitous language is about getting the whole team (both domain experts and developers) to communicate more transparently
+ using a domain model.
+
+* Meanwhile, model-driven design is about capturing that model in a very straightforward manner in code.
+
+Let's look at each in turn.
+
+=== Creating a Ubiquitous Language
+
+ It's no secret that the IT industry is plagued by project failures. Too often systems take longer than intended to implement, and when finally implemented, they don't address the real requirements anyway.
+
+ Over the years we in IT have tried various approaches to address this
+ failing. Using waterfall methodologies, we've asked for requirements to
+ be fully and precisely written down before starting on anything
+ else.Waterfall methodologies Or, using
+ agile methodologies, we've realized that requirements are likely to
+ change anyway and have sought to deliver systems incrementally using
+ feedback loops to refine the implementation.Agile methodologies
+
+ But let's not get distracted talking about methodologies. At the end
+ of the day what really matters is communication between the domain
+ experts (that is, the business) who need the system and the techies
+ actually implementing it. If the two don't have and cannot evolve a
+ shared understanding of what is required, then the chance of delivering
+ a useful system will be next to nothing.Ubiquitous language
+
+ Bridging this gap is traditionally what business analysts are for;
+ they act as interpreters between the domain experts and the developers.
+ However, this still means there are two (or more) languages in use,
+ making it difficult to verify that the system being built is correct. If
+ the analyst mistranslates a requirement, then neither the domain expert
+ nor the application developer will discover this until (at best) the
+ application is first demonstrated or (much worse) an end user sounds
+ the alarm once the application has been deployed into production.
+
+ Rather than trying to translate between a business language and a
+ technical language, with _D_ we aim to have the
+ business and developers using the same terms for the same concepts in order to
+ create a single <firstuse>domain model</firstuse>.Domain-driven design (DDD)</i> This domain model
+ identifies the relevant concepts of the domain, how they relate, and
+ ultimately where the responsibilities are. This single domain model
+ provides the vocabulary for the *e* for our
+ system.<footnote>
+ <p>In Extreme Programming, there is a similar idea called
+ a *s*. But *e* is much more
+ evocative.</p>
+ </footnote></p>
+
+ <ddd>
+ <title>Ubiquitous Language</title>
+
+ <p>Build a common language between the domain experts and developers
+ by using the concepts of the domain model as the primary means of
+ communication. Use the terms in speech, in diagrams, in writing, and when
+ presenting.</p>
+
+ <p>If an idea cannot be expressed using this set of concepts, then go
+ back and extend the model. Look for and remove ambiguities and
+ inconsistencies.</p>
+ </ddd>
+
+ <p>Creating a *e* calls upon everyone involved in the system's development
+ to express what they are doing through the vocabulary provided by the
+ model. If this can't be done, then our model is incomplete. Finding the
+ missing words deepens our understanding of the domain being modeled.</p>
+
+ <p>This might sound like nothing more than me insisting that the
+ developers shouldn't use jargon when talking to the business. Well,
+ that's true enough, but it's not a one-way street. A *e* demands that the developers work hard to understand the
+ problem domain, but it also demands that the business works hard in
+ being *e* in its naming and descriptions of those
+ concepts. After all, ultimately the developers will have to express
+ those concepts in a computer programming language.</p>
+
+ Also, although here I'm talking about the "domain experts" as being a
+ homogeneous group of people, often they may come from different branches
+ of the business. Even if we weren't building a computer system, there's a
+ lot of value in helping the domain experts standardize their own
+ terminology.<i>Domain experts</i> Is the marketing department's "prospect" the same as sales'
+ "customer," and is that the same as an after-sales<layout>\break{}</layout> "contract"?</p>
+
+ <p>The need for precision within the *e*
+ also helps us scope the system.<i>Domain-driven design (DDD)</i><i>Scoping the system</i> Most business processes evolve piecemeal
+ and are often quite ill-defined. If the domain experts have a very good
+ idea of what the business process should be, then that's a good
+ candidate for automation, that is, including it in the scope of the
+ system. But if the domain experts find it hard to agree, then it's
+ probably best to leave it out. After all, human beings are rather more
+ capable of dealing with fuzzy situations than computers.</p>
+
+ <p>So, if the development team (business and developers together)
+ continually searches to build their *e*,
+ then the domain model naturally becomes richer as the nuances of the
+ domain are uncovered. At the same time, the knowledge of the business
+ domain experts also deepens as edge conditions and contradictions that
+ have previously been overlooked are explored.</p>
+
+ <p>We use the *e* to build up a domain
+ model. But what do we do *h* that model? The answer to
+ that is the second of our central ideas.<i startref="idx.gettingstarted1">Domain-driven design (DDD)</i><i startref="idx.gettingstarted2">Ubiquitous language</i></p>
+
+ <sect2>
+ <title>Model-Driven Design</title>
+
+ <p>Of the various methodologies that the IT industry has tried, many
+ advocate the production of separate analysis models and implementation
+ models. <i class="StartOfRange" id="idx.gettingstarted3">Model-driven design</i> A recent example is that of the _G_'s Model-Driven Architecture (_A_) initiative, with its
+ platform-independent model (the _M_) and a
+ platform-specific model (the _M_).<i>Model-driven design</i></p>
+
+ <p>Bah and humbug! If we use our *e* just
+ to build up a high-level analysis model, then we will re-create the
+ communication divide. The domain experts and business analysts will look
+ only to the analysis model, and the developers will look only to the
+ implementation model. Unless the mapping between the two is completely
+ mechanical, inevitably the two will diverge.<i>Analysis model</i><i>Implementation model</i></p>
+
+ <p>What do we mean by *l* anyway?<i>Domain-driven design (DDD)</i> For some, the term will bring to
+ mind _L_ class or sequence diagrams and the like. But
+ this isn't a model; it's a visual *n* of some
+ aspect of a model. No, a domain model is a group of related concepts,
+ identifying them, naming them, and defining how they relate. What is in
+ the model depends on what our objective is. We're not looking to simply
+ model everything that's out there in the real world. Instead, we want to
+ take a relevant abstraction or simplification of it and then make it do
+ something useful for us. Oft quoted and still true is that a model is neither
+ right nor wrong, just more or less useful.</p>
+
+ <p>For our *e* to have value, the domain
+ model that encodes it must have a straightforward, literal
+ representation to the design of the software, specifically to the implementation. Our
+ software's design should be driven by this model; we should have a
+ *n*.</p>
+
+ <ddd>
+ <title>Model-Driven Design</title>
+
+ <p>There must be a straightforward and very literal way to represent
+ the domain model in terms of software. The model should balance these
+ two requirements: form the *e* of the
+ development team and be representable in code.<i>Domain model</i></p>
+
+ <p>Changing the code means changing the model; refining the model
+ requires a change to the code.</p>
+ </ddd>
+
+ <p>Here also the word *n* might mislead; some might again be
+ thinking of design documents and design diagrams.<i>Model-driven design</i><i>Design</i> But by *n* we mean
+ a way of organizing the domain concepts, which in turn leads to the way
+ in which we organize their representation in code.</p>
+
+ <p>Luckily, using <firstuse>object-oriented</firstuse>
+ (_O_) languages such as Java, this is relatively easy
+ to do; _O_ is based on a modeling paradigm anyway.<i>Model-driven design</i> We
+ can express domain concepts using classes and interfaces, and we can
+ express the relationships between those concepts using associations.<i>Object-oriented (OO) languages</i></p>
+ </sect2>
+
+ <p>So far so good. Or maybe, so far so much motherhood and apple pie.
+ Understanding the _D_ concepts isn't the same as being
+ able to apply them, and some of the _D_ ideas can be
+ difficult to put into practice. What this book is about is how Naked
+ Objects eases that path by applying these central ideas of
+ _D_ in a very concrete way. So, now would be a good time
+ to see how.<i startref="idx.gettingstarted3">Model-driven design</i></p>
-### Ubiquitous Language
-IMPORTANT: TODO
+## Naked Objects Pattern
-yada yada yada
+Apache Isis implements the naked objects pattern, originally formulated by Richard Pawson. So who better than Richard to explain the origination of the idea?
+[TIP]
+====
+The Naked Objects pattern arose, at least in part, from my own
+frustration at the lack of success of the domain-driven approach. Good examples
+were hard to find--as they are still.
+
+A common complaint from _DDD_ practitioners was that it
+was hard to gain enough commitment from business stakeholders, or even to
+engage them at all. My own experience suggested that it was nearly
+impossible to engage business managers with _UML_ diagrams.
+It was much easier to engage them in rapid prototyping--where they could
+see and interact with the results--but most forms of rapid prototyping
+concentrate on the presentation layer, often at the expense of the
+underlying model and certainly at the expense of abstract thinking.
+
+Even if you could engage the business sponsors sufficiently to design a
+domain model, by the time you'd finished developing the system on top of the
+domain model, most of its benefits had disappeared. It's all very well
+creating an agile domain object model, but if any change to that model
+also dictates the modification of one or more layers underneath it (dealing
+with persistence) and multiple layers on top (dealing with presentation),
+then that agility is practically worthless.
+
+The other concern that gave rise to the birth of Naked Objects was how to
+make user interfaces of mainstream business systems more "expressive"--how
+to make them feel more like using a drawing program or
+_CAD_ system. Most business systems are not at all
+expressive; they treat the user merely as a dumb
+*process-follower*, rather than as an empowered
+*problem-solver*. Even the so-called usability experts had little
+to say on the subject: try finding the word "empowerment" or any synonym
+thereof in the index of any book on usability. Research had demonstrated
+that the best way to achieve expressiveness was to create an object-oriented
+user interface (_OOUI_). In practice, though, __OOUI__s were notoriously hard to develop.
+
+Sometime in the late 1990s, it dawned on me that if the domain model
+really did represent the "ubiquitous language" of the
+business and those domain objects were behaviorally rich (that is,
+business logic is encapsulated as methods on the domain objects rather than
+in procedural scripts on top of them), then the _UI_ could
+be nothing more than a reflection of the user interface. This would solve
+both of my concerns. It would make it easier to do domain-driven design,
+because one could instantly translate evolving domain modeling ideas
+into a working prototype. And it would deliver an expressive,
+object-oriented user interface for free. Thus was born the idea of Naked
+Objects.
+
+-- Richard Pawson, from the foreword to Dan Haywood's "Domain Driven Design using Naked Objects"
+====
-## Naked Objects Pattern
[TIP]
.Object Interface Mapping
[2/2] isis git commit: ISIS-1133: more documentation.
Posted by da...@apache.org.
ISIS-1133: more documentation.
Project: http://git-wip-us.apache.org/repos/asf/isis/repo
Commit: http://git-wip-us.apache.org/repos/asf/isis/commit/3f14ded5
Tree: http://git-wip-us.apache.org/repos/asf/isis/tree/3f14ded5
Diff: http://git-wip-us.apache.org/repos/asf/isis/diff/3f14ded5
Branch: refs/heads/ISIS-1133
Commit: 3f14ded5ab8d9b57743f671d4dc01d8bf1c6c77f
Parents: 143f190
Author: Dan Haywood <da...@haywood-associates.co.uk>
Authored: Thu Apr 30 13:51:57 2015 +0100
Committer: Dan Haywood <da...@haywood-associates.co.uk>
Committed: Thu Apr 30 13:51:57 2015 +0100
----------------------------------------------------------------------
.../asciidoc/user-guide/_/GettingStarted.adoc | 947 +++++++++++++++++++
.../user-guide/_user-guide_core-concepts.adoc | 12 +-
...user-guide_core-concepts_apache-isis-vs.adoc | 14 -
...ser-guide_core-concepts_building-blocks.adoc | 3 +
.../_user-guide_core-concepts_philosophy.adoc | 294 ++++++
.../_user-guide_core-concepts_principles.adoc | 291 +-----
...core-concepts_principles_apache-isis-vs.adoc | 14 +
...de_getting-started_datanucleus-enhancer.adoc | 2 +-
8 files changed, 1278 insertions(+), 299 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_/GettingStarted.adoc
----------------------------------------------------------------------
diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_/GettingStarted.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_/GettingStarted.adoc
new file mode 100644
index 0000000..5194136
--- /dev/null
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_/GettingStarted.adoc
@@ -0,0 +1,947 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<!DOCTYPE chapter SYSTEM "local/xml/markup.dtd">
+= Getting Started
+
+
+
+To stop himself from procrastinating in his work, the Greek orator Demosthenes
+would shave off half his beard. Too embarrassed to go outside and with
+nothing else to do, his work got done.
+
+We could learn a lesson or two from old Demosthenes. After all, we
+forever seem to be taking an old concept and inventing a new technology
+around it (always remembering to invent a new acronym, of course)---anything,
+it would seem, instead of getting down to the real work of solving business
+problems.
+
+Domain-driven design (hereafter _DDD_) puts the emphasis
+elsewhere, "tackling complexity in the heart of software." And Naked
+Objects---an open source Java framework---helps you build your business
+applications with ease. No beard shaving necessary, indeed.
+
+In this chapter, we're going to briefly describe the key ideas underlying
+_DDD_, identify some of the challenges of applying these
+ideas, and see for ourselves how Naked Objects makes our task that much
+easier.
+
+== Understanding Domain-Driven Design
+
+
+
+There's no doubt that we developers love the challenge of understanding
+and deploying complex technologies. But understanding the nuances and
+subtleties of the business domain itself is just as great a challenge,
+perhaps more so. If we devoted our efforts to understanding and addressing
+those subtleties, we could build better, cleaner, and more maintainable
+software that did a better job for our stakeholders. And there's no doubt
+that our stakeholders would thank us for it.
+
+A couple of years back Eric Evans wrote his book 'Domain-Driven Design', which is well on its way to
+becoming a seminal work. In fact, most if not all of the ideas in Evans'
+book have been expressed before, but what he did was pull those ideas
+together to show how predominantly object-oriented techniques can be used
+to develop rich, deep, insightful, and ultimately useful business
+applications.
+
+So, let's start off by reviewing the essential ideas of
+_DDD_.
+
+
+== The Essentials of DDD
+
+
+
+There are two central ideas at the heart of domain-driven design. The
+*_ubiquitous language_* is about getting the whole team
+(both domain experts and developers) to communicate more transparently
+using a domain model. Meanwhile, *_model-driven design_*
+is about capturing that model in a very straightforward manner in code.
+Let's look at each in turn.
+
+=== Creating a Ubiquitous Language
+
+
+
+It's no secret that the IT industry is plagued by project
+failures. Too
+often systems take longer than intended to implement, and when finally
+implemented, they don't address the real requirements anyway.
+
+Over the years we in IT have tried various approaches to address this
+failing. Using waterfall methodologies, we've asked for requirements to
+be fully and precisely written down before starting on anything
+else. Or, using
+agile methodologies, we've realized that requirements are likely to
+change anyway and have sought to deliver systems incrementally using
+feedback loops to refine the implementation.
+
+But let's not get distracted talking about methodologies. At the end
+of the day what really matters is communication between the domain
+experts (that is, the business) who need the system and the techies
+actually implementing it. If the two don't have and cannot evolve a
+shared understanding of what is required, then the chance of delivering
+a useful system will be next to nothing.
+
+Bridging this gap is traditionally what business analysts are for;
+they act as interpreters between the domain experts and the developers.
+However, this still means there are two (or more) languages in use,
+making it difficult to verify that the system being built is correct. If
+the analyst mistranslates a requirement, then neither the domain expert
+nor the application developer will discover this until (at best) the
+application is first demonstrated or (much worse) an end user sounds
+the alarm once the application has been deployed into production.
+
+Rather than trying to translate between a business language and a
+technical language, with _DDD_ we aim to have the
+business and developers using the same terms for the same concepts in order to
+create a single *_domain model_*. This domain model
+identifies the relevant concepts of the domain, how they relate, and
+ultimately where the responsibilities are. This single domain model
+provides the vocabulary for the *ubiquitous language* for our
+system.
+
+[TIP]
+=====
+
+In Extreme Programming, there is a similar idea called
+a *system of names*. But *ubiquitous language* is much more
+evocative.
+
+====
+
+
+
+==
+
+.Ubiquitous Language
+****
+
+Build a common language between the domain experts and developers
+by using the concepts of the domain model as the primary means of
+communication. Use the terms in speech, in diagrams, in writing, and when
+presenting.
+
+If an idea cannot be expressed using this set of concepts, then go
+back and extend the model. Look for and remove ambiguities and
+inconsistencies.
+
+****
+
+
+
+Creating a *ubiquitous
+language* calls upon everyone involved in the system's development
+to express what they are doing through the vocabulary provided by the
+model. If this can't be done, then our model is incomplete. Finding the
+missing words deepens our understanding of the domain being modeled.
+
+This might sound like nothing more than me insisting that the
+developers shouldn't use jargon when talking to the business. Well,
+that's true enough, but it's not a one-way street. A *ubiquitous
+language* demands that the developers work hard to understand the
+problem domain, but it also demands that the business works hard in
+being *precise* in its naming and descriptions of those
+concepts. After all, ultimately the developers will have to express
+those concepts in a computer programming language.
+
+Also, although here I'm talking about the "domain experts" as being a
+homogeneous group of people, often they may come from different branches
+of the business. Even if we weren't building a computer system, there's a
+lot of value in helping the domain experts standardize their own
+terminology. Is the marketing department's "prospect" the same as sales'
+"customer," and is that the same as an after-sales "contract"?
+
+The need for precision within the *ubiquitous language*
+also helps us scope the system. Most business processes evolve piecemeal
+and are often quite ill-defined. If the domain experts have a very good
+idea of what the business process should be, then that's a good
+candidate for automation, that is, including it in the scope of the
+system. But if the domain experts find it hard to agree, then it's
+probably best to leave it out. After all, human beings are rather more
+capable of dealing with fuzzy situations than computers.
+
+So, if the development team (business and developers together)
+continually searches to build their *ubiquitous language*,
+then the domain model naturally becomes richer as the nuances of the
+domain are uncovered. At the same time, the knowledge of the business
+domain experts also deepens as edge conditions and contradictions that
+have previously been overlooked are explored.
+
+We use the *ubiquitous language* to build up a domain
+model. But what do we do *with* that model? The answer to
+that is the second of our central ideas.
+
+
+=== Model-Driven Design
+
+
+
+Of the various methodologies that the IT industry has tried, many
+advocate the production of separate analysis models and implementation
+models. A recent example is that of the _OMG_'s Model-Driven Architecture ( _MDA_) initiative, with its
+platform-independent model (the _PIM_) and a
+platform-specific model (the _PSM_).
+
+Bah and humbug! If we use our *ubiquitous language* just
+to build up a high-level analysis model, then we will re-create the
+communication divide. The domain experts and business analysts will look
+only to the analysis model, and the developers will look only to the
+implementation model. Unless the mapping between the two is completely
+mechanical, inevitably the two will diverge.
+
+What do we mean by *model* anyway? For some, the term will bring to
+mind _UML_ class or sequence diagrams and the like. But
+this isn't a model; it's a visual *representation* of some
+aspect of a model. No, a domain model is a group of related concepts,
+identifying them, naming them, and defining how they relate. What is in
+the model depends on what our objective is. We're not looking to simply
+model everything that's out there in the real world. Instead, we want to
+take a relevant abstraction or simplification of it and then make it do
+something useful for us. Oft quoted and still true is that a model is neither
+right nor wrong, just more or less useful.
+
+For our *ubiquitous language* to have value, the domain
+model that encodes it must have a straightforward, literal
+representation to the design of the software, specifically to the implementation. Our
+software's design should be driven by this model; we should have a
+*model-driven design*.
+
+==
+
+.Model-Driven Design
+****
+
+There must be a straightforward and very literal way to represent
+the domain model in terms of software. The model should balance these
+two requirements: form the *ubiquitous language* of the
+development team and be representable in code.
+
+Changing the code means changing the model; refining the model
+requires a change to the code.
+
+****
+
+
+
+Here also the word *design* might mislead; some might again be
+thinking of design documents and design diagrams. But by *design* we mean
+a way of organizing the domain concepts, which in turn leads to the way
+in which we organize their representation in code.
+
+Luckily, using *_object-oriented_*
+( _OO_) languages such as Java, this is relatively easy
+to do; _OO_ is based on a modeling paradigm anyway. We
+can express domain concepts using classes and interfaces, and we can
+express the relationships between those concepts using associations.
+
+
+So far so good. Or maybe, so far so much motherhood and apple pie.
+Understanding the _DDD_ concepts isn't the same as being
+able to apply them, and some of the _DDD_ ideas can be
+difficult to put into practice. What this book is about is how Naked
+Objects eases that path by applying these central ideas of
+_DDD_ in a very concrete way. So, now would be a good time
+to see how.
+
+
+== Introducing Naked Objects
+
+
+
+*_Naked Objects_* is both an architectural pattern and a software
+framework. The pattern was originally conceived and articulated by Richard
+Pawson as a means of engaging business stakeholders and experts in
+developing more expressive domain-driven applications. Richard discusses this in more
+detail in the foreword.
+
+The framework, then, is an implementation of the pattern to help you
+rapidly prototype, develop, and deploy domain-driven applications:
+
+
+* *Rapid prototyping* comes from the fact that you can
+develop an application without spending any time writing user
+interface code or persistence code. This creates a very tight feedback
+loop with your domain experts.
+
+
+* The *development support* comes from the close
+integration with developer tools such as *_Eclipse_* (for coding),
+*_FitNesse_* (for testing), *_Maven_* (for building and packaging), and *_Hudson_*
+(for continuous integration).
+
+
+* The *deployment support* comes from Naked Objects'
+pluggable architecture allowing different viewers, persistence
+mechanisms, and security. In fact, the domain
+model has no runtime dependencies on the framework, so you can deploy
+your application on any Java-based enterprise architecture with any
+_UI_ you want.
+
+
+
+For more on the original philosophy that drove Naked Objects'
+development, see Richard Pawson and Robert Matthews' book, 'Naked Objects', and Richard's later PhD thesis.
+
+[TIP]
+=====
+
+link:http://www.nakedobjects.org/downloads/Pawson%20thesis.pdf[]
+
+====
+
+
+
+==
+
+.How Does Naked Objects Compare to Other Frameworks?
+****
+
+Many other frameworks promise rapid application
+development and provide automatically generated user interfaces, so how
+do they compare to Naked Objects?
+
+Some of most significant are *_Rails_* (for the Ruby programming
+language), *_Grails_* (Groovy), and *_Spring Roo_* (Java with AspectJ).
+
+[TIP]
+=====
+
+The frameworks mentioned here are hosted at
+link:http://rubyonrails.org/[], link:http://www.grails.org[],
+and link:http://www.springsource.org/roo[].
+
+====
+
+These frameworks all use the classic *model-view-controller* ( _MVC_)
+pattern for web applications, with scaffolding, code-generation,
+and/or metaprogramming tools for the controllers and views, as well as
+convention over configuration to define how these components
+interact. The views provided out of the box by these frameworks tend to be
+simple _CRUD_-style interfaces. More sophisticated
+behavior is accomplished by customizing the generated controllers.
+
+For many developers, the most obvious difference of Naked Objects is
+its deliberate lack of an explicit controller layer;
+non- _CRUD_ behavior is automatically made available in
+its generic object-oriented _UI_s. More sophisticated
+UIs can be built either by skinning Naked Objects (see <<chp.IWWF>>) or by using a newer viewer that supports
+easy customization (see <<chp.DTFR>>).
+
+Like all of these frameworks, Naked Objects can expose domain
+objects as a _RESTful_ web service. However, it has some other tricks you
+may not find in a typical _MVC_ framework:
+it supports client-server (rich-client) deployments as well as on the Web;
+it supports non- _RDBMS_ as well as
+_RDBMS_ object stores, with an in-memory object store
+for rapid prototyping; it supports domain-driven concepts such as
+values, repositories, and domain services; it supports agile scenario
+testing using FitNesse; and it puts the domain
+metamodel at the center, allowing the programming model to be
+redefined.
+****
+
+I could talk at length in a highly theoretical fashion about Naked
+Objects and how it relates to _DDD_ for the next thirty
+pages, but what we're going to do instead is see Naked Objects in
+action.
+
+
+== Naked Objects in About Five Minutes
+
+
+
+Throughout the book we're going to be using Naked Objects 4.0 for Java,
+an open source framework licensed under Apache License v2.
+
+[TIP]
+=====
+
+link:http://www.apache.org/licenses/LICENSE-2.0.html[]
+
+====
+
+All the other products we're going to use in this book are
+also open source with similar nonrestrictive licenses. Without further
+ado, let's get our development environment set up.
+
+[TIP]
+=====
+
+If you have any problems setting up or running the application,
+don't forget the book's forum as a place to get help.
+
+====
+
+
+
+
+=== Set Up the Development Environment
+
+
+
+Naked Objects is a Java framework, so we need Java 5 or higher
+installed along with an _IDE_. In this book I'm going
+to be using Eclipse 3.5: it's extremely capable and freely available.
+However, there's nothing stopping you from using some other _IDE_.
+
+In addition, we need to set up Maven, one of the most commonly used
+tools for building Java software.
+
+[TIP]
+=====
+
+Maven is hosted at link:http://maven.apache.org[].
+
+====
+
+Naked Objects provides a Maven archetype (a project
+template) to help get us started, and the case study we'll develop
+through the book builds on this archetype and so is also a Maven-based
+project. We won't be using particularly advanced features of Maven, but
+if you are interested in learning more, then take a look at 'Maven, The Definitive Guide'.
+
+We also need Maven support in our _IDE_ (or at least
+the ability to import Maven projects). In the case of Eclipse, this
+means installing a plug-in; if you're using an _IDE_
+other than Eclipse, then make sure it has equivalent Maven support. Both
+NetBeans 6.7 onward and IntelliJ IDEA 7.0 onward have out-of-the-box
+support, so there's plenty of choice.
+
+And finally, we also need to download the Naked Objects distribution
+itself. We don't need this for the Naked Objects
+_JAR_s---we'll get those courtesy of Maven---but the
+distribution does include a number of resources (such as icons) that we
+will need, along with an example application that we're going to try
+in the next section.
+
+So, do the following:
+
+
+* Install Java 5 or 6 from link:http://java.sun.com[]. Either
+the _JRE_ or the _JDK_ is fine. I used
+_JDK_ 1.5_014 for this book. Set the
+`JAVA_HOME` environment variable, and
+update the `PATH` to include
+`$JAVA_HOME/``bin`.
+
+
+* Download and install Maven 2.0.9 or higher, from
+link:http://maven.apache.org/download.html[]. The Maven website
+has instructions on installing Maven, but it basically amounts to
+extracting the _ZIP_, setting up the
+`M2_HOME` environment variable, and
+updating your `PATH` to pick up the
+`mvn.bat` or `mvn.sh` batch
+file.
+
+
+* Download and unzip Eclipse 3.5 or higher,
+link:http://www.eclipse.org/downloads[]. You can use either the
+standard distribution or the full-blown Java EE enterprise distribution.
+
+
+* Install the *m2eclipse* plug-ins into Eclipse, v0.9.7 or higher,
+link:http://m2eclipse.sonatype.org/update[]. This is an update
+site from which Eclipse can download and install the software. If
+you aren't an Eclipse regular, the incantation is: select the Help > Install
+New Software menu and then press the Add… button to add
+this site.
+
+
+* Download Naked Objects 4.0 from
+link:https://sourceforge.net/projects/nakedobjects/[]; the file
+you need is `nakedobjects-4.0.0-for-maven.zip`
+(or whichever is the latest release). Unzip this wherever you want;
+I'll refer to this location as `$NO_HOME` (though
+there's no need to set an environment variable).
+
+
+
+
+Included in the Naked Objects download are a number of Eclipse
+templates that we can use to quickly write short code fragments using
+Content Assist (that is,
+kbd:[Ctrl]+kbd:[Spacebar]). We won't need
+these until the next chapter, but now is a good time to set them up. So,
+start up Eclipse in a new workspace, select Window >
+Preferences > Java > Editor > Templates, and then select Import.
+Navigate to the
+`$NO_HOME/resources/ide/``eclipse/templates` directory,
+and select the `nakedobjects-templates.xml` file.
+Finally, hit OK.
+
+Note, by the way, that these templates are effectively stored in the
+workspace; if you use File > Switch Workspace, then you'll need to
+reimport the templates. For easy reference, all the templates are
+listed in <<apx.ET>>. When we get to using them, I'll also
+indicate some of the main ones to use in the text.
+
+OK, let's test our setup by importing and running a very simple
+claims-processing application written using Naked Objects.
+
+
+=== Import and Explore a Naked Objects Application
+
+
+
+With Eclipse still running, first make sure you are in the Java
+perspective (use Window > Open Perspective > Other > Java).
+Then, use File > Import > General > Maven Projects, and browse
+to `$NO_HOME/examples/``claims`. Hit Enter, and a set of
+Maven projects should be listed.
+
+==
+
+.The imported `dom` project
+
+image::images/eps/TheImportedDomProject.eps[]
+
+
+
+Now hit Finish, and you should be left with a parent project (no
+suffix) and five further child projects with various suffices. This is the
+standard way that we tend to organize Naked Objects applications:
+
+
+* The `dom` (domain object model) is where most of
+the action is, containing the domain classes that make up the
+application.
+
+
+* The `fixture` project contains fixtures that
+provide a working set of objects for demonstration purposes; we
+cover this in <<chp.RP>>.
+
+
+* The `service` project provides supporting
+services to the domain objects; we cover this mostly in <<chp.IIS>> and in <<chp.IWTD>>.
+
+
+* The `commandline` project is where we run the
+application from during development (throughout the book).
+
+
+* The `webapp` project allows us to deploy the
+application to a web container; we use this at the end of the book,
+in <<chp.DTFR>>.
+
+
+
+Open the `dom` project, as shown in <<sec.TheImportedDomProject>>. There should be three concrete
+classes: `Employee`, `Claim`,
+and `ClaimItem`. `Employee`s
+make `Claim`s, and `Claim`s
+are made up of `ClaimItem`s. In addition, there are
+some interfaces implemented by these domain classes
+(`Approver` and `Claimant`),
+as well as some repository interfaces
+(`EmployeeRepository` and
+`ClaimRepository`). These are used to look up
+`Employee`s and, um,
+`Claim`s; the implementations are in the
+`services` project.
+
+Poke around inside these domain classes. We are of course
+going to be covering how to write such classes in detail (starting in
+<<chp.ITDC>>), but for now it should at easy enough to see
+that an `Employee` has a
+`Name` and an
+`Approver` property:
+
+[source,java]
+----
+include::code/chapter01/Employee.java
+----
+
+==
+
+.The claims app in the DnD viewer
+
+image::images/eps/TheSampleAppInTheDndViewer.eps[]
+
+
+Now here's the thing: the domain model we've been looking at is the
+entire application. Fundamentally, writing a Naked Objects application
+means writing a domain model, and that's it.
+
+
+It's time to run the application, methinks.
+
+
+=== Run the Application
+
+
+
+Naked Objects is so called because it automatically displays the
+domain objects in an *_object-oriented user interface_*
+( _OOUI_). These _OOUI_s are also
+generic because they can display *any* domain object in a
+standardized fashion.
+
+Out of the box, Naked Objects ships with two main
+_OOUI_ viewers. The *_drag-n-drop_*
+( _DnD_) viewer is a rich client intended for
+client-side deployment, while the _HTML_ viewer is
+designed to host your application on the Web. Let's look at the
+_DnD_ viewer first.
+
+==
+
+.The claims app in the HTML viewer
+
+image::images/eps/TheSampleAppInTheHtmlViewer.eps[]
+
+
+In Eclipse, use Run > Run Configurations to bring up the generated
+launch configurations. Listed as a Java Application launch configuration
+should be `claims_exploration_dnd.launch` (defined
+in the `commandline` project). Select this, and then
+click Run. If using another _IDE_, all we are doing is
+running `org.nakedobjects.runtime.NakedObjects`
+with a command-line option of `--type exploration --viewer
+dnd`.
+
+All being well, the _DnD_ viewer should launch,
+showing the two repositories as icons. By right-clicking these icons,
+we can invoke actions on the repositories to retrieve objects. Once we
+have an object, we can use it to navigate to other referenced objects
+(click/double-click icons), right-click to invoke actions, and
+generally have a good old browse around. We can see the
+_DnD_ viewer in action in <<sec.TheSampleAppInTheDndViewer>>.
+
+
+OK, let's now run the same application using the
+_HTML_ viewer. Again, using Run > Run Configurations,
+this time select `claims_exploration_html.``launch`,
+and click Run. Again, if using another IDE, this is running the same
+class with flags of `--type exploration` and `--viewer
+html`.
+
+What Naked Objects will do is run the application on an embedded
+Jetty web server, listening on port 8080. If for some reason you need to
+use another port number, just edit the
+`nakedobjects.embedded-web-server.port`
+property in the
+`config/embedded-web-server.properties` file in the
+`commandline` project.
+
+Eclipse's console view should indicate that the server is up and
+running. Now start your favorite web browser, and go to
+link:http://localhost:8080/logon.app[]. You should be logged in
+automatically and then see links representing the two repositories;
+these are the _HTML_ equivalents of the icons in the
+_DnD_ desktop view. Click one of these, and then use
+the action links to navigate the application as before. We can see the
+_HTML_ viewer in action in <<sec.TheSampleAppInTheHtmlViewer>>.
+
+Try running the two viewers side-by-side. Although they look
+different, they both provide the same functionality, and that
+functionality is defined entirely by the domain classes.
+
+We're going to be using both of these viewers extensively throughout
+the book; they are, after all, the default viewers provided by Naked
+Objects. I should point out, though, that these aren't the only viewers
+available. In <<chp.DTFR>>, we'll see a number of other
+viewers either developed or in active development. It's also possible to
+use a custom interface; see <<chp.IWWF>>.
+
+
+Before our quick Naked Objects demo, I was asserting that putting
+_DDD_ ideas into practice isn't necessarily that easy
+but that Naked Objects eases the path. Now that you've seen Naked Objects "in
+the flesh" (so to speak!), let's see how.
+
+
+== How Naked Objects Helps with DDD
+
+
+
+The case for _DDD_ might be compelling, but that
+doesn't necessarily make it easy to do. Let's take a look at some of the
+challenges that _DDD_ throws up and see how Naked Objects
+helps address them.
+
+=== DDD Takes a Conscious Effort
+
+
+
+Here's what Evans says about *ubiquitous language*: "With
+a conscious effort by the [development] team the domain model can
+provide the backbone for [the] common [ubiquitous] language...connecting team communication to the software implementation."
+
+The word I want to pick up on here is *conscious*. It takes a
+*conscious* effort by the entire team to develop the
+*ubiquitous language*. Everyone in the team must challenge the use of new
+or unfamiliar terms, must clarify concepts when used in a new context, and
+in general must be on the lookout for sloppy thinking. This takes
+willingness on the part of all involved, not to mention some practice.
+
+With Naked Objects, though, the *ubiquitous language*
+evolves with scarcely any effort at all. For the business experts, the
+Naked Objects viewers show the domain concepts they identify and the
+relationships between those concepts in a straightforward fashion.
+Meanwhile, the developers can devote themselves to encoding those domain
+concepts directly as domain classes. There's no technology to get
+distracted by; there is literally nothing else for the developers to
+work on.
+
+
+=== DDD Must Be Grounded
+
+
+
+Employing a *model-driven design* isn't necessarily
+straightforward, and the development processes used by some
+organizations positively hinder it. It's not sufficient for the business
+analysts or architects to come up with some idealized representation of
+the business domain and then chuck it over the wall for the programmers
+to do their best with.
+
+Instead, the concepts in the model must have a very literal
+representation in code. If we fail to do this, then we open up the
+communication divide, and our *ubiquitous language* is lost.
+There is literally no point having a domain model that cannot be
+represented in code. We cannot invent our *ubiquitous
+language* in a vacuum, and the developers must ensure that the
+model remains grounded in the doable.
+
+In Naked Objects, we have a very pure one-to-one correspondence between the
+domain concepts and its implementation. Domain concepts are represented
+as classes and interfaces, easily demonstrated back to the business. If
+the model is clumsy, then the application will be clumsy too, and so the
+team can work together to find a better implementable model.
+
+
+=== Abstract Models Are Difficult to Represent
+
+
+
+If we are using code as the primary means of expressing the model,
+then we need to find a way to make this model understandable to the
+business.
+
+We could generate _UML_ diagrams and the like from
+code. That will work for some members of the business community, but not
+for everyone. Or we could generate a _PDF_
+document from Javadoc comments, but comments aren't code and so the
+document may be inaccurate. Anyway, even if we do create such a
+document, not everyone will read it.
+
+A better way to represent the model is to show it in action as a
+working prototype. As we've seen, Naked Objects enables this with ease.
+Such prototypes bring the domain model to life, engaging the
+audience in a way that a piece of paper never can.
+
+Moreover, with Naked Objects prototypes, the domain model will come
+shining through. If there are mistakes or misunderstandings in the
+domain model, they will be obvious to all.
+
+
+=== Layered Architectures Are Expensive and Easily
+Compromised
+
+
+
+==
+
+.Layered Architecture
+****
+
+We partition a complex program into layers, with each layer
+cohesive and depending only on the layers below.
+
+In particular, we have a layer dedicated to the domain model. The
+code in this layer is unencumbered with the (mostly technical)
+responsibilities of the other layers and so can evolve to tackle
+complex domains as well as simple ones.
+
+****
+
+
+
+_DDD_ rightly requires that the domain model lives
+in its own layer within the architecture. The other layers of the application (usually presentation, application, and persistence)
+have their own responsibilities, and are completely separate.
+
+
+
+
+However, there are two immediate issues. The first is rather obvious:
+custom coding each of those other layers is an expensive proposition.
+Picking up on the previous point, this in itself can put the kibosh on
+using prototyping to represent the model, even if we wanted to do so.
+
+The second issue is more subtle. It takes real skill to ensure the
+correct separation of concerns between these layers, if indeed you can
+get an agreement as to what those concerns actually are. Even with the
+best intentions, it's all too easy for custom-written layers to blur the
+boundaries and put (for example) validation in the user interface layer
+when it should belong to the domain layer. At the other extreme, it's
+quite possible for custom layers to distort or completely subvert the
+underlying domain model.
+
+
+
+Because of Naked Objects' generic _OOUI_s, there's
+no need to write the other layers of the architecture. And as we've
+seen, this makes prototyping cheap. But more than that, there will be no
+leakage of concerns outside the domain model. All the validation logic
+*must* be in the domain model because there is
+nowhere else to put it.
+
+Moreover, although Naked Objects does provide a
+complete runtime framework, there is no direct coupling of your domain
+model to the framework. That means it is very possible to take
+your domain model prototyped in Naked Objects and then deploy it on
+some other _J(2)EE_ architecture, with a custom
+_UI_ if you want. Naked Objects guarantees that your
+domain model is complete.
+
+
+=== Naked Objects Extends the Reach of DDD
+
+
+
+Domain-driven design is often positioned as being applicable only to
+complex domains; indeed, the subtitle of Evans book is *Tackling
+Complexity in the Heart of Software*. The corollary is that DDD is
+overkill for simpler domains. The trouble is that we immediately have to
+make a choice: is the domain complex enough to warrant a domain-driven
+approach?
+
+This goes back to the previous point, building and maintaining a
+*layered architecture*. It doesn't seem cost effective to go to all the
+effort of a DDD approach if the underlying domain is simple.
+
+However, with Naked Objects, we don't write these other layers, so
+we don't have to make a call on how complex our domain is. We can
+start working solely on our domain, even if we suspect it will be
+simple. If it is indeed a simple domain, then there's no hardship, but if unexpected subtleties arise, then we're in a good position to
+handle them.
+
+
+If you're just starting out writing domain-driven applications, then
+Naked Objects should significantly ease your journey into applying
+_DDD_. On the other hand, if you've used
+_DDD_ for a while, then you should find Naked Objects a
+very useful new tool in your arsenal.
+
+In this chapter we've discussed DDD in the context of a layered
+architecture. We're going to finish off this chapter with a refinement
+of that idea, which moreover will act as a road map to the
+rest of the book.
+
+
+== The Big Picture
+
+
+
+A few years ago Alistair Cockburn reworked the traditional layered
+architecture diagram and came up with the
+*_hexagonal architecture_*, as shown in <<sec.HexagonalArchitecture>>.
+
+[TIP]
+=====
+
+link:http://alistair.cockburn.us/Hexagonal+architecture[].
+Another similar (same?) pattern is the onion architecture; see
+link:http://jeffreypalermo.com/blog/the-onion-architecture-part-3/[].
+
+====
+
+
+
+==
+
+.The *hexagonal architecture* emphasizes multiple implementations of
+the different layers.
+
+image::images/eps/HexagonalArchitecture.eps[]
+
+
+What Cockburn is emphasizing is that there's usually more than one way
+*into* an application (what he called the *_user-side'
+ports_*) and more than one way *out of* an
+application too (the *_data-side ports_*). This is very similar to the
+concept of primary and secondary actors in use cases: a primary actor
+(often a human user but not always) is active and initiates an
+interaction, while a secondary actor (almost always an external system) is
+passive and waits to be interacted with.
+
+Associated with each port can be an *_adapter_* (in
+fact, Cockburn's alternative name for this architecture is *_ports and
+adapters_*). An adapter is a device (piece of software) that talks in the
+protocol (or _API_) of the port. Each port could have
+several adapters.
+
+Naked Objects maps very nicely onto the *hexagonal architecture*. As
+shown in <<sec.HexagonalArchitectureForNakedObjects>>, most
+of the user-side adapters (that is, viewers) run in the same memory space
+as the domain layer and so (using Cockburn's terminology) access the
+domain layer through an in-memory port. However, rich client/desktop-based
+viewers such as the _DnD_ viewer can also access the
+domain layer using a remoting protocol port. Naked Objects also supports
+_RESTful_ web services, which I've drawn as
+an adapter, but one could also think of it as an implementation of a third
+port providing access to other non-Java on the user side. An inbound adapter from
+an *_enterprise service bus_* ( _ESB_)
+could also consume events from any other system in the enterprise.
+
+==
+
+.The *hexagonal architecture* for Naked Objects
+
+image::images/eps/HexagonalArchitectureForNakedObjects.eps[]
+
+
+For the data side, we are mostly concerned with persisting domain
+objects to some sort of object store; this is the persistence port. We
+might also invoke services; the implementation of these services is
+specific to the application. These could, for example, call out to an
+external web service. Alternatively, the service could be a generic
+mechanism to publish events asynchronously onto an ESB, removing any
+runtime dependency between our application and the external system.
+
+Doing double duty, <<sec.HexagonalArchitectureForNakedObjects>> is a road map for the book; as you might have guessed, the
+overlaid numbers correspond to the chapters where that component is
+discussed. As you would expect, much of the book (most of the chapters in
+Parts I and II) is focused on the domain model. The chapters in
+Part III focus more on the adapters (viewers and object stores) that
+interact with the domain model.
+
+
+== Coming Up Next
+
+
+
+In this chapter, we talked about the two central ideas of
+domain-driven design, that of the *ubiquitous language* and of
+a *model-driven design*. We also got our development
+environment up and running and used it to run our first Naked Objects
+application. We then looked at how Naked Objects addresses several issues
+that you might otherwise struggle with when applying
+_DDD_ and recast the traditional *layered architecture*
+instead as the *hexagonal architecture*.
+
+This is very much a learning-by-doing book. Throughout, we're going to
+be developing our own domain application as a single case study, so in
+the next chapter we're going to start at the beginning, identifying the
+main concepts of its domain. See you there.
+
+
+== Exercises
+
+
+
+In each chapter of the book there is an "Exercises" section like this,
+where I'll be asking you to implement the techniques covered in the
+chapter text.
+
+In addition to the case study in the main text, you might want to
+develop your own application alongside, something that's close to your
+heart. So, get your thinking hat on and decide what you'd like to implement
+as your first Naked Objects (and perhaps domain-driven design)
+application. In the next chapter's exercises, you'll be in a position to
+start implementing it.
+
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts.adoc
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diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts.adoc
index 8078d8d..0280e4c 100644
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts.adoc
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts.adoc
@@ -3,18 +3,14 @@
:_basedir: ../
:_imagesdir: images/
-IMPORTANT: TODO
+This introductory chapter should give you a good about what Apache Isis actually *is*: the fundamental ideas and principles that it builds upon, how it compares with other frameworks, what the fundamental building blocks are for actually writing an Isis application, and what services and features the framework provides for you to leverage in your own apps.
-include::_user-guide_core-concepts_principles.adoc[leveloffset=+1]
+include::_user-guide_core-concepts_philosophy.adoc[leveloffset=+1]
-include::_user-guide_core-concepts_apache-isis-vs.adoc[leveloffset=+1]
+include::_user-guide_core-concepts_principles.adoc[leveloffset=+1]
include::_user-guide_core-concepts_building-blocks.adoc[leveloffset=+1]
-include::_user-guide_core-concepts_framework-provided-services.adoc[leveloffset=+2]
-
-
-## Honouring the Single Responsibility Principle
+include::_user-guide_core-concepts_framework-provided-services.adoc[leveloffset=+1]
-### Behaviourally Complete vs Contributions
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_apache-isis-vs.adoc
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deleted file mode 100644
index c64344a..0000000
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_apache-isis-vs.adoc
+++ /dev/null
@@ -1,14 +0,0 @@
-= Apache Isis vs ...
-:Notice: Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at. http://www.apache.org/licenses/LICENSE-2.0 . Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
-:_basedir: ../
-:_imagesdir: images/
-
-IMPORTANT: TODO
-
-## vs Spring
-
-## vs JEE
-
-## vs Grails
-
-## vs Angular
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_building-blocks.adoc
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diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_building-blocks.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_building-blocks.adoc
index 50044a0..0c04071 100644
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_building-blocks.adoc
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_building-blocks.adoc
@@ -232,3 +232,6 @@ public String getId()
----
This method returns a logical identifier for a service, independent of its implementation. Currently it used only by perspectives, providing a label by which to record the services that are available for a current user's profile. <!--See ? for more about profiles and perspectives.-->
+
+
+
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_philosophy.adoc
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diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_philosophy.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_philosophy.adoc
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--- /dev/null
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_philosophy.adoc
@@ -0,0 +1,294 @@
+= Philosophy and Architecture
+:Notice: Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at. http://www.apache.org/licenses/LICENSE-2.0 . Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
+:_basedir: ../
+:_imagesdir: images/
+
+This section describes some of the core ideas and architectural patterns upon which Apache Isis builds.
+
+== Domain-Driven Design
+
+There's no doubt that we developers love the challenge of understanding
+and deploying complex technologies. But understanding the nuances and
+subtleties of the business domain itself is just as great a challenge,
+perhaps more so. If we devoted our efforts to understanding and addressing
+those subtleties, we could build better, cleaner, and more maintainable
+software that did a better job for our stakeholders. And there's no doubt
+that our stakeholders would thank us for it.
+
+A couple of years back Eric Evans wrote his book link:http://www.amazon.co.uk/Domain-driven-Design-Tackling-Complexity-Software/dp/0321125215[Domain-Driven Design], which is well on its way to
+becoming a seminal work. In fact, most if not all of the ideas in Evans'
+book have been expressed before, but what he did was pull those ideas
+together to show how predominantly object-oriented techniques can be used
+to develop rich, deep, insightful, and ultimately useful business
+applications.
+
+There are two central ideas at the heart of domain-driven design.
+
+* the *_ubiquitous language_* is about getting the whole team (both domain experts
+ and developers) to communicate more transparently using a domain model.
+
+* Meanwhile, *_model-driven design_* is about capturing that model in a
+ very straightforward manner in code.
+
+Let's look at each in turn.
+
+=== Ubiquitous Language
+
+It's no secret that the IT industry is plagued by project failures. Too
+often systems take longer than intended to implement, and when finally
+implemented, they don't address the real requirements anyway.
+
+Over the years we in IT have tried various approaches to address this
+failing. Using waterfall methodologies, we've asked for requirements to
+be fully and precisely written down before starting on anything
+else. Or, using
+agile methodologies, we've realized that requirements are likely to
+change anyway and have sought to deliver systems incrementally using
+feedback loops to refine the implementation.
+
+But let's not get distracted talking about methodologies. At the end
+of the day what really matters is communication between the domain
+experts (that is, the business) who need the system and the techies
+actually implementing it. If the two don't have and cannot evolve a
+shared understanding of what is required, then the chance of delivering
+a useful system will be next to nothing.
+
+Bridging this gap is traditionally what business analysts are for;
+they act as interpreters between the domain experts and the developers.
+However, this still means there are two (or more) languages in use,
+making it difficult to verify that the system being built is correct. If
+the analyst mistranslates a requirement, then neither the domain expert
+nor the application developer will discover this until (at best) the
+application is first demonstrated or (much worse) an end user sounds
+the alarm once the application has been deployed into production.
+
+Rather than trying to translate between a business language and a
+technical language, with _DDD_ we aim to have the
+business and developers using the same terms for the same concepts in order to
+create a single *_domain model_*. This domain model
+identifies the relevant concepts of the domain, how they relate, and
+ultimately where the responsibilities are. This single domain model
+provides the vocabulary for the ubiquitous language for our
+system.
+
+.Ubiquitous Language
+****
+Build a common language between the domain experts and developers
+by using the concepts of the domain model as the primary means of
+communication. Use the terms in speech, in diagrams, in writing, and when
+presenting.
+
+If an idea cannot be expressed using this set of concepts, then go
+back and extend the model. Look for and remove ambiguities and
+inconsistencies.
+****
+
+
+
+Creating a ubiquitous language calls upon everyone involved in the system's development
+to express what they are doing through the vocabulary provided by the
+model. If this can't be done, then our model is incomplete. Finding the
+missing words deepens our understanding of the domain being modeled.
+
+This might sound like nothing more than me insisting that the
+developers shouldn't use jargon when talking to the business. Well,
+that's true enough, but it's not a one-way street. A *ubiquitous
+language* demands that the developers work hard to understand the
+problem domain, but it also demands that the business works hard in
+being *precise* in its naming and descriptions of those
+concepts. After all, ultimately the developers will have to express
+those concepts in a computer programming language.
+
+Also, although here I'm talking about the "domain experts" as being a
+homogeneous group of people, often they may come from different branches
+of the business. Even if we weren't building a computer system, there's a
+lot of value in helping the domain experts standardize their own
+terminology. Is the marketing department's "prospect" the same as sales'
+"customer," and is that the same as an after-sales "contract"?
+
+The need for precision within the ubiquitous language
+also helps us scope the system. Most business processes evolve piecemeal
+and are often quite ill-defined. If the domain experts have a very good
+idea of what the business process should be, then that's a good
+candidate for automation, that is, including it in the scope of the
+system. But if the domain experts find it hard to agree, then it's
+probably best to leave it out. After all, human beings are rather more
+capable of dealing with fuzzy situations than computers.
+
+So, if the development team (business and developers together)
+continually searches to build their ubiquitous language,
+then the domain model naturally becomes richer as the nuances of the
+domain are uncovered. At the same time, the knowledge of the business
+domain experts also deepens as edge conditions and contradictions that
+have previously been overlooked are explored.
+
+We use the ubiquitous language to build up a domain
+model. But what do we do *with* that model? The answer to
+that is the second of our central ideas.
+
+
+=== Model-Driven Design
+
+Of the various methodologies that the IT industry has tried, many
+advocate the production of separate analysis models and implementation
+models. One example (from the mid 2000s) was that of the _OMG_'s Model-Driven Architecture ( _MDA_) initiative, with its
+platform-independent model (the _PIM_) and a
+platform-specific model (the _PSM_).
+
+Bah and humbug! If we use our ubiquitous language just
+to build up a high-level analysis model, then we will re-create the
+communication divide. The domain experts and business analysts will look
+only to the analysis model, and the developers will look only to the
+implementation model. Unless the mapping between the two is completely
+mechanical, inevitably the two will diverge.
+
+What do we mean by *model* anyway? For some, the term will bring to
+mind _UML_ class or sequence diagrams and the like. But
+this isn't a model; it's a visual *representation* of some
+aspect of a model. No, a domain model is a group of related concepts,
+identifying them, naming them, and defining how they relate. What is in
+the model depends on what our objective is. We're not looking to simply
+model everything that's out there in the real world. Instead, we want to
+take a relevant abstraction or simplification of it and then make it do
+something useful for us. Oft quoted and still true is that a model is neither
+right nor wrong, just more or less useful.
+
+For our ubiquitous language to have value, the domain
+model that encodes it must have a straightforward, literal
+representation to the design of the software, specifically to the implementation. Our
+software's design should be driven by this model; we should have a
+model-driven design.
+
+
+.Model-Driven Design
+****
+There must be a straightforward and very literal way to represent
+the domain model in terms of software. The model should balance these
+two requirements: form the ubiquitous language of the
+development team and be representable in code.
+
+Changing the code means changing the model; refining the model
+requires a change to the code.
+****
+
+
+Here also the word *design* might mislead; some might again be
+thinking of design documents and design diagrams. But by *design* we mean
+a way of organizing the domain concepts, which in turn leads to the way
+in which we organize their representation in code.
+
+Luckily, using *_object-oriented_*
+( _OO_) languages such as Java, this is relatively easy
+to do; _OO_ is based on a modeling paradigm anyway. We
+can express domain concepts using classes and interfaces, and we can
+express the relationships between those concepts using associations.
+
+
+So far so good. Or maybe, so far so much motherhood and apple pie.
+Understanding the _DDD_ concepts isn't the same as being
+able to apply them, and some of the _DDD_ ideas can be
+difficult to put into practice. What this book is about is how Naked
+Objects eases that path by applying these central ideas of
+_DDD_ in a very concrete way. So, now would be a good time
+to see how.
+
+
+
+
+== Naked Objects Pattern
+
+Apache Isis implements the naked objects pattern, originally formulated by Richard Pawson. So who better than Richard to explain the origination of the idea?
+
+=== Origin of the Naked Objects Pattern, Richard Pawson
+
+The Naked Objects pattern arose, at least in part, from my own
+frustration at the lack of success of the domain-driven approach. Good examples
+were hard to find--as they are still.
+
+A common complaint from _DDD_ practitioners was that it
+was hard to gain enough commitment from business stakeholders, or even to
+engage them at all. My own experience suggested that it was nearly
+impossible to engage business managers with _UML_ diagrams.
+It was much easier to engage them in rapid prototyping--where they could
+see and interact with the results--but most forms of rapid prototyping
+concentrate on the presentation layer, often at the expense of the
+underlying model and certainly at the expense of abstract thinking.
+
+Even if you could engage the business sponsors sufficiently to design a
+domain model, by the time you'd finished developing the system on top of the
+domain model, most of its benefits had disappeared. It's all very well
+creating an agile domain object model, but if any change to that model
+also dictates the modification of one or more layers underneath it (dealing
+with persistence) and multiple layers on top (dealing with presentation),
+then that agility is practically worthless.
+
+The other concern that gave rise to the birth of Naked Objects was how to
+make user interfaces of mainstream business systems more "expressive"--how
+to make them feel more like using a drawing program or
+_CAD_ system. Most business systems are not at all
+expressive; they treat the user merely as a dumb
+*process-follower*, rather than as an empowered
+*problem-solver*. Even the so-called usability experts had little
+to say on the subject: try finding the word "empowerment" or any synonym
+thereof in the index of any book on usability. Research had demonstrated
+that the best way to achieve expressiveness was to create an object-oriented
+user interface (_OOUI_). In practice, though, __OOUI__s were notoriously hard to develop.
+
+Sometime in the late 1990s, it dawned on me that if the domain model
+really did represent the "ubiquitous language" of the
+business and those domain objects were behaviorally rich (that is,
+business logic is encapsulated as methods on the domain objects rather than
+in procedural scripts on top of them), then the _UI_ could
+be nothing more than a reflection of the user interface. This would solve
+both of my concerns. It would make it easier to do domain-driven design,
+because one could instantly translate evolving domain modeling ideas
+into a working prototype. And it would deliver an expressive,
+object-oriented user interface for free. Thus was born the idea of Naked
+Objects.
+
+[TIP]
+====
+Taken from Richard Pawson's foreword to Dan Haywood's "Domain Driven Design using Naked Objects"
+====
+
+You can learn much more about the pattern in Richard's PhD on the subject.
+
+
+=== Object Interface Mapping
+
+Another ways to think about the naked objects pattern is as an _object interface mapper_, or `OIM`.
+
+Just as an ORM (such as link:http://datanucleus.org[DataNucleus] or link:http:hibernate.org[Hibernate]) maps domain entities to a database, you can think of the naked objects pattern as representing the concept of mapping domain objects to a user interface.
+
+
+== Hexagonal Architecture
+
+Originally described by Alistair Cockburn, the link:http://alistair.cockburn.us/Hexagonal+architecture[Hexagonal Architecture] ...
+
+[TIP]
+====
+The hexagonal architecture is also known as the link:http://c2.com/cgi/wiki?PortsAndAdaptersArchitecture:[Ports and Adapters] architecture or (less frequently) as the link:http://jeffreypalermo.com/blog/the-onion-architecture-part-1/[Onion] architecture.
+====
+
+
+== Aspect Oriented
+
+Although not implemented using an aspect-oriented language such as AspectJ, Isis takes considerable inspiration from AOP concepts.
+
+For example, the UI visualization automatically provided by Isis can be thought of (and is!) treating the UI as a cross-cutting concern.
+
+Isis' also has support for traits/mixins through its <<Contributions>>. This allows functionality from one class (a domain service) to be rendered as if it belongs to another (a domain object).
+
+
+* aspect-oriented design, such as traits/mix-ins (see <<Contributions>>) and interceptors and UI visualization as a cross-cutting concern
+
+
+== DCI
+
+IMPORTANT: TODO ... Trygve Reenskaug
+
+
+
+
+include::_user-guide_core-concepts_principles_apache-isis-vs.adoc[leveloffset=+1]
+
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
----------------------------------------------------------------------
diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
index 014a0b9..42079f6 100644
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles.adoc
@@ -1,277 +1,16 @@
-= Principles
+= Principles and Values
:Notice: Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at. http://www.apache.org/licenses/LICENSE-2.0 . Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
:_basedir: ../
:_imagesdir: images/
-IMPORTANT: TODO
+This section describes some of the core principles and values that the framework aims to honour and support.
-== Domain-Driven Design
-There's no doubt that we developers love the challenge of understanding
-and deploying complex technologies. But understanding the nuances and
-subtleties of the business domain itself is just as great a challenge,
-perhaps more so. If we devoted our efforts to understanding and addressing
-those subtleties, we could build better, cleaner, and more maintainable
-software that did a better job for our stakeholders. And there's no doubt
-that our stakeholders would thank us for it.
+== Decoupled (no "Big Ball of Mud")
-A couple of years back Eric Evans wrote his book Domain-Driven Design</bookname>, which is well on its way to
-becoming a seminal work. In fact, most if not all of the ideas in Evans'
-book have been expressed before, but what he did was pull those ideas
-together to show how predominantly object-oriented techniques can be used
-to develop rich, deep, insightful, and ultimately useful business
-applications.
+IMPORTANT: TODO ...
-So, let's start off by reviewing the essential ideas of DDD.
-
-=== The Essentials of DDD
-
-There are two central ideas at the heart of domain-driven design.
-
-* The ubiquitous language is about getting the whole team (both domain experts and developers) to communicate more transparently
- using a domain model.
-
-* Meanwhile, model-driven design is about capturing that model in a very straightforward manner in code.
-
-Let's look at each in turn.
-
-=== Creating a Ubiquitous Language
-
- It's no secret that the IT industry is plagued by project failures. Too often systems take longer than intended to implement, and when finally implemented, they don't address the real requirements anyway.
-
- Over the years we in IT have tried various approaches to address this
- failing. Using waterfall methodologies, we've asked for requirements to
- be fully and precisely written down before starting on anything
- else.Waterfall methodologies Or, using
- agile methodologies, we've realized that requirements are likely to
- change anyway and have sought to deliver systems incrementally using
- feedback loops to refine the implementation.Agile methodologies
-
- But let's not get distracted talking about methodologies. At the end
- of the day what really matters is communication between the domain
- experts (that is, the business) who need the system and the techies
- actually implementing it. If the two don't have and cannot evolve a
- shared understanding of what is required, then the chance of delivering
- a useful system will be next to nothing.Ubiquitous language
-
- Bridging this gap is traditionally what business analysts are for;
- they act as interpreters between the domain experts and the developers.
- However, this still means there are two (or more) languages in use,
- making it difficult to verify that the system being built is correct. If
- the analyst mistranslates a requirement, then neither the domain expert
- nor the application developer will discover this until (at best) the
- application is first demonstrated or (much worse) an end user sounds
- the alarm once the application has been deployed into production.
-
- Rather than trying to translate between a business language and a
- technical language, with _D_ we aim to have the
- business and developers using the same terms for the same concepts in order to
- create a single <firstuse>domain model</firstuse>.Domain-driven design (DDD)</i> This domain model
- identifies the relevant concepts of the domain, how they relate, and
- ultimately where the responsibilities are. This single domain model
- provides the vocabulary for the *e* for our
- system.<footnote>
- <p>In Extreme Programming, there is a similar idea called
- a *s*. But *e* is much more
- evocative.</p>
- </footnote></p>
-
- <ddd>
- <title>Ubiquitous Language</title>
-
- <p>Build a common language between the domain experts and developers
- by using the concepts of the domain model as the primary means of
- communication. Use the terms in speech, in diagrams, in writing, and when
- presenting.</p>
-
- <p>If an idea cannot be expressed using this set of concepts, then go
- back and extend the model. Look for and remove ambiguities and
- inconsistencies.</p>
- </ddd>
-
- <p>Creating a *e* calls upon everyone involved in the system's development
- to express what they are doing through the vocabulary provided by the
- model. If this can't be done, then our model is incomplete. Finding the
- missing words deepens our understanding of the domain being modeled.</p>
-
- <p>This might sound like nothing more than me insisting that the
- developers shouldn't use jargon when talking to the business. Well,
- that's true enough, but it's not a one-way street. A *e* demands that the developers work hard to understand the
- problem domain, but it also demands that the business works hard in
- being *e* in its naming and descriptions of those
- concepts. After all, ultimately the developers will have to express
- those concepts in a computer programming language.</p>
-
- Also, although here I'm talking about the "domain experts" as being a
- homogeneous group of people, often they may come from different branches
- of the business. Even if we weren't building a computer system, there's a
- lot of value in helping the domain experts standardize their own
- terminology.<i>Domain experts</i> Is the marketing department's "prospect" the same as sales'
- "customer," and is that the same as an after-sales<layout>\break{}</layout> "contract"?</p>
-
- <p>The need for precision within the *e*
- also helps us scope the system.<i>Domain-driven design (DDD)</i><i>Scoping the system</i> Most business processes evolve piecemeal
- and are often quite ill-defined. If the domain experts have a very good
- idea of what the business process should be, then that's a good
- candidate for automation, that is, including it in the scope of the
- system. But if the domain experts find it hard to agree, then it's
- probably best to leave it out. After all, human beings are rather more
- capable of dealing with fuzzy situations than computers.</p>
-
- <p>So, if the development team (business and developers together)
- continually searches to build their *e*,
- then the domain model naturally becomes richer as the nuances of the
- domain are uncovered. At the same time, the knowledge of the business
- domain experts also deepens as edge conditions and contradictions that
- have previously been overlooked are explored.</p>
-
- <p>We use the *e* to build up a domain
- model. But what do we do *h* that model? The answer to
- that is the second of our central ideas.<i startref="idx.gettingstarted1">Domain-driven design (DDD)</i><i startref="idx.gettingstarted2">Ubiquitous language</i></p>
-
- <sect2>
- <title>Model-Driven Design</title>
-
- <p>Of the various methodologies that the IT industry has tried, many
- advocate the production of separate analysis models and implementation
- models. <i class="StartOfRange" id="idx.gettingstarted3">Model-driven design</i> A recent example is that of the _G_'s Model-Driven Architecture (_A_) initiative, with its
- platform-independent model (the _M_) and a
- platform-specific model (the _M_).<i>Model-driven design</i></p>
-
- <p>Bah and humbug! If we use our *e* just
- to build up a high-level analysis model, then we will re-create the
- communication divide. The domain experts and business analysts will look
- only to the analysis model, and the developers will look only to the
- implementation model. Unless the mapping between the two is completely
- mechanical, inevitably the two will diverge.<i>Analysis model</i><i>Implementation model</i></p>
-
- <p>What do we mean by *l* anyway?<i>Domain-driven design (DDD)</i> For some, the term will bring to
- mind _L_ class or sequence diagrams and the like. But
- this isn't a model; it's a visual *n* of some
- aspect of a model. No, a domain model is a group of related concepts,
- identifying them, naming them, and defining how they relate. What is in
- the model depends on what our objective is. We're not looking to simply
- model everything that's out there in the real world. Instead, we want to
- take a relevant abstraction or simplification of it and then make it do
- something useful for us. Oft quoted and still true is that a model is neither
- right nor wrong, just more or less useful.</p>
-
- <p>For our *e* to have value, the domain
- model that encodes it must have a straightforward, literal
- representation to the design of the software, specifically to the implementation. Our
- software's design should be driven by this model; we should have a
- *n*.</p>
-
- <ddd>
- <title>Model-Driven Design</title>
-
- <p>There must be a straightforward and very literal way to represent
- the domain model in terms of software. The model should balance these
- two requirements: form the *e* of the
- development team and be representable in code.<i>Domain model</i></p>
-
- <p>Changing the code means changing the model; refining the model
- requires a change to the code.</p>
- </ddd>
-
- <p>Here also the word *n* might mislead; some might again be
- thinking of design documents and design diagrams.<i>Model-driven design</i><i>Design</i> But by *n* we mean
- a way of organizing the domain concepts, which in turn leads to the way
- in which we organize their representation in code.</p>
-
- <p>Luckily, using <firstuse>object-oriented</firstuse>
- (_O_) languages such as Java, this is relatively easy
- to do; _O_ is based on a modeling paradigm anyway.<i>Model-driven design</i> We
- can express domain concepts using classes and interfaces, and we can
- express the relationships between those concepts using associations.<i>Object-oriented (OO) languages</i></p>
- </sect2>
-
- <p>So far so good. Or maybe, so far so much motherhood and apple pie.
- Understanding the _D_ concepts isn't the same as being
- able to apply them, and some of the _D_ ideas can be
- difficult to put into practice. What this book is about is how Naked
- Objects eases that path by applying these central ideas of
- _D_ in a very concrete way. So, now would be a good time
- to see how.<i startref="idx.gettingstarted3">Model-driven design</i></p>
-
-
-## Naked Objects Pattern
-
-Apache Isis implements the naked objects pattern, originally formulated by Richard Pawson. So who better than Richard to explain the origination of the idea?
-
-[TIP]
-====
-The Naked Objects pattern arose, at least in part, from my own
-frustration at the lack of success of the domain-driven approach. Good examples
-were hard to find--as they are still.
-
-A common complaint from _DDD_ practitioners was that it
-was hard to gain enough commitment from business stakeholders, or even to
-engage them at all. My own experience suggested that it was nearly
-impossible to engage business managers with _UML_ diagrams.
-It was much easier to engage them in rapid prototyping--where they could
-see and interact with the results--but most forms of rapid prototyping
-concentrate on the presentation layer, often at the expense of the
-underlying model and certainly at the expense of abstract thinking.
-
-Even if you could engage the business sponsors sufficiently to design a
-domain model, by the time you'd finished developing the system on top of the
-domain model, most of its benefits had disappeared. It's all very well
-creating an agile domain object model, but if any change to that model
-also dictates the modification of one or more layers underneath it (dealing
-with persistence) and multiple layers on top (dealing with presentation),
-then that agility is practically worthless.
-
-The other concern that gave rise to the birth of Naked Objects was how to
-make user interfaces of mainstream business systems more "expressive"--how
-to make them feel more like using a drawing program or
-_CAD_ system. Most business systems are not at all
-expressive; they treat the user merely as a dumb
-*process-follower*, rather than as an empowered
-*problem-solver*. Even the so-called usability experts had little
-to say on the subject: try finding the word "empowerment" or any synonym
-thereof in the index of any book on usability. Research had demonstrated
-that the best way to achieve expressiveness was to create an object-oriented
-user interface (_OOUI_). In practice, though, __OOUI__s were notoriously hard to develop.
-
-Sometime in the late 1990s, it dawned on me that if the domain model
-really did represent the "ubiquitous language" of the
-business and those domain objects were behaviorally rich (that is,
-business logic is encapsulated as methods on the domain objects rather than
-in procedural scripts on top of them), then the _UI_ could
-be nothing more than a reflection of the user interface. This would solve
-both of my concerns. It would make it easier to do domain-driven design,
-because one could instantly translate evolving domain modeling ideas
-into a working prototype. And it would deliver an expressive,
-object-oriented user interface for free. Thus was born the idea of Naked
-Objects.
-
--- Richard Pawson, from the foreword to Dan Haywood's "Domain Driven Design using Naked Objects"
-====
-
-
-[TIP]
-.Object Interface Mapping
-====
-Just as an ORM (such as link:http://datanucleus.org[DataNucleus] or link:http:hibernate.org[Hibernate]) maps domain entities to a database, you can think of Naked Objects as an OIM - mapping domain objects to a user interface.
-====
-
-* multiple UIs.
-
-
-
-## Hexagonal Architecture
-
-Originally described by Alistair Cockburn, the link:http://alistair.cockburn.us/Hexagonal+architecture[Hexagonal Architecture] ...
-
-[TIP]
-====
-The hexagonal architecture is also known as the link:http://c2.com/cgi/wiki?PortsAndAdaptersArchitecture:[Ports and Adapters] architecture or (less frequently) as the link:http://jeffreypalermo.com/blog/the-onion-architecture-part-1/[Onion] architecture.
-====
-
-
-
-## Decoupled Modules
+Long-term Cost of ownership
Using:
@@ -280,29 +19,29 @@ Using:
* an in-memory event bus
* applib
-.Aspect Oriented
-****
-Although not implemented using an aspect-oriented language such as AspectJ, Isis takes considerable inspiration from AOP concepts.
-For example, the UI visualization automatically provided by Isis can be thought of (and is!) treating the UI as a cross-cutting concern.
+== Honouring the Single Responsibility Principle
-Isis' also has support for traits/mixins through its <<Contributions>>. This allows functionality from one class (a domain service) to be rendered as if it belongs to another (a domain object).
+=== Behaviourally Complete vs Contributions
-* aspect-oriented design, such as traits/mix-ins (see <<Contributions>>) and interceptors and UI visualization as a cross-cutting concern
-****
-
-## Focuses on its Key Responsibilities
+== Focuses on its Key Responsibilities
* Isis is at heart a metamodel with runtime, and coordinates interations using an AOP set of principles
* Apache Isis vs Isis Addons
* Apache Isis vs Shiro vs DataNucleus
+[NOTE]
+====
+... we're getting there...
+====
+
+
-## Testable Applications
+== Testable Applications
While Apache Isis can be used (very effectively) for simple CRUD-style applications, it is also intended to be used for complex business domains. Ensuring that the business logic in such applications is correct means that the framework must (and does) provide robust testing support, both for developer-level unit testing and business-level (end-to-end) integration testing.
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles_apache-isis-vs.adoc
----------------------------------------------------------------------
diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles_apache-isis-vs.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles_apache-isis-vs.adoc
new file mode 100644
index 0000000..c64344a
--- /dev/null
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_core-concepts_principles_apache-isis-vs.adoc
@@ -0,0 +1,14 @@
+= Apache Isis vs ...
+:Notice: Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at. http://www.apache.org/licenses/LICENSE-2.0 . Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
+:_basedir: ../
+:_imagesdir: images/
+
+IMPORTANT: TODO
+
+## vs Spring
+
+## vs JEE
+
+## vs Grails
+
+## vs Angular
http://git-wip-us.apache.org/repos/asf/isis/blob/3f14ded5/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_getting-started_datanucleus-enhancer.adoc
----------------------------------------------------------------------
diff --git a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_getting-started_datanucleus-enhancer.adoc b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_getting-started_datanucleus-enhancer.adoc
index c0d6c4a..a015a4e 100644
--- a/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_getting-started_datanucleus-enhancer.adoc
+++ b/adocs/documentation/src/main/asciidoc/user-guide/_user-guide_getting-started_datanucleus-enhancer.adoc
@@ -60,7 +60,7 @@ If working from the Maven command line, JDO enhancement is done using the `maven
The <<SimpleApp Archetype>> sets up the plugin correctly in the `dom` (domain object model) module. (It's actually a little bit more complext to cater for users of the Eclipse IDE using Eclipse's m2e plugin).
-=== `META-INF/persistence.xml`
+== `META-INF/persistence.xml`
It's also a good idea to ensure that the `dom` module has a JDO `META-INF/persistence.xml` file: