ECO Boot Camp

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ECO Boot Camp

• Malcolm Groves
• mgroves_at_borland.com

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Agenda

• Overview
• Model
• Classes, Attributes, Methods, Associations
• Derived Attributes OCL, Code, Reverse Derived
• Derived Associations
• Association Classes
• ECO Packages

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Agenda

• ECOSpace
• Persistence
• Transactions
• User Interface
• ReferenceHandle, ExpressionHandle,
  CurrencyManagerhandle
• Variables
• Forms
• Extender Components

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Agenda

• ECO II
• Other Resources

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ECO Overview
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Database-Driven Development
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Database-Driven Development

• Advantages
• Familiar
• Low barrier to entry
• Disadvantages
• Typically, low cohesion of business logic
• Maintenance

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Model-Driven Development
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Model-Driven Development

• Advantages
• Maintenance
• Documentation
• Higher Cohesion of Business Logic
• Disadvantages
• Higher barrier to entry
• Lots of plumbing code to be written
• Objects lt-gt DB
• UI lt-gt Objects
• Collections

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Enterprise Core Objects

• ECO is still Model-Driven Development
• More automation
• Database Mapping
• UI Mapping
• Associations
• OCL in your model
• Derived Attributes, Associations
• Constraints
• Services
• Undu/Redo, AutoForms, etc

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ECO

• Advantages
• Maintenance
• Productivity
• Nice, clean separation of concerns
• Disadvantages
• Requires a little bit of a mindset change
• Addictive ?

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Demo

• ECO Overview

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Remember

• Dont lose sight of the fact that you are still
  just designing Delphi classes

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Model Basics

• Example
• Classes
• Attributes
• Operations
• Associations
• Generalization

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Beyond the Basics
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Derived Attributes

• Sometimes, an attribute is not simply some value
  stored in a database
• Eg Rect.Area Rect.Width Rect.Height
• Similar to Calculated Fields in TTable
• How to derive the value?
• OCL (Object Constraint Language)
• Code

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Derived Attributes

• Examples
• Using OCL to derive an attributes value
• Using Code to derive an attributes value
• Overriding Derived Attributes
• Reverse Derived Attributes

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Derived Associations

• Sometimes an Association can be calculated from
  another
• Eg. Customer.Accounts gt Customer.OverdueAccounts
• Use OCL to return the other end of the
  association
• Example

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Question

• Where would you put a StartDate attribute?
• On the Person?
• What happens when they get a new job? Or have two
  jobs?
• On the Company?
• What happens when the Company hires a second
  person?
• On the Association?

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Association Classes

• Association Classes let you place attributes,
  methods, etc on an association
• Extremely flexible, powerful concept
• Once you start using it, it will explain a whole
  bunch of problems you used to experience.
• Example

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Association Classes

• On the Model

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Association Classes

• In Sourcecode

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UML Packages

• Default behaviour of ECO is to put all domain
  classes in a single file
• Not very good for Team Development
• Not very good for manageability
• UML Packages let you group related classes
  together in separate files
• Shortcuts let you still interact with these
  classes in other diagrams
• Example

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Model Summary

• Classes, Attributes, Methods, Associations
• Derived Attributes OCL, CODE, Reverse Derived
• Derived Associations
• Association Classes
• ECO Packages

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EcoSpace

• Runtime container for your objects
• Manages
• Object Lifecycle (ie. it creates, and destroys
  your objects)
• Persistence
• Executes OCL
• Object Transactions
• Etc

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ECOSpace
Fred Person
Mary Person
ABC123 Invoice
Mary Person
ABC123 Invoice
ABC123 Invoice
Depends on the Datastore chosen
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Services

• Persistence
• Relationships
• Transactions
• Subscriptions
• Caching
• Querying
• Undo / Redo
• Versioning

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Persistence

• PersistenceMapper component
• XML
• BDP
• SQLServer
• ECOSpace.UpdateDatabase
• Transient Objects
• Example

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Transactions

• Nothing to do with Database Transactions, these
  are Object Transactions
• Used in a similar fashion to DB Transactions
• EcoSpace.UndoService.StartTransaction
• try
•   // Code that does stuff to objects here
•   EcoSpace.UndoService.CommitTransaction
• except
•   EcoSpace.UndoService.RollbackTransaction
•   raise
• end

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User Interface
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Handles

• ReferenceHandle
• Connection between your UI Controls and your
  ECOSpace
• ExpressionHandle
• Executes OCL and returns one or more values
• Implements IList so can be used as a DataSource
  for Databinding

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Handles

• CurrencyManagerHandle
• Acts as a cursor into a collection of Objects
• Example
• VariableHandle
• Allows you to create dynamic OCL
• Example

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VariableHandle Flow of Components
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ECO From Sourcecode

• Creating an Object
• Getting a Reference To The Currently Selected
  Object
• Creating Objects Part 2
• Executing OCL from Code

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Forms

• AutoForms
• ECO can automatically generate a form based on
  the model
• Great during development, you probably wouldnt
  deploy them ?
• Custom Forms
• Custom Auto Forms

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Extender Components

• Delphi 8 ECO ships with a number of components to
  remove the need for common coding
• ECOAutoFormExtender
• ECOActionExtender
• ECOListActionExtender
• ECODragDropExtender
• Like anything, use them once you know what they
  do for you.

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Summary

• Model
• Classes, Attributes, Methods, Associations
• Derived Attributes OCL, Code, Reverse Derived
• Derived Associations
• Association Classes
• ECO Packages
• ECOSpace
• Persistence
• Transactions
• User Interface
• ReferenceHandle, ExpressionHandle,
  CurrencyManagerhandle
• Variables
• Forms
• Extender Components

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But wait, theres more

• This was an introduction
• Should be enough for you to start exploring
• ECO is very rich, and there is plenty for you to
  get into
• Constraints, Subscriptions, other Services,
  Optimistic Locking,
• ECO II is even richer

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ECO II

• Ships in Diamondback
• Everything you learned today is still applicable
• Adds
• ASP.NET Support (Web Forms and Web Services)
• Legacy Database Support
• Synchronization Server
• Concurrency
• Improved Designer
• Come to Monday night Meet the Delphi Team for a
  Sneak Preview

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Other Resources

• My Blog
• http//blogs.borland.com/malcolmgroves
• ECO Tutorials
• http//www.borland.com/delphi_net/architect/eco/tu
  torial/
• Christophe Flourys Technical Whitepaper
• http//www.borland.com/products/white_papers/del_u
  nleashing_enterprise_models_with_delphi_for_dotnet
  .html

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Other Resources

• Newsgroups
• borland.public.delphi.modeldrivenarchitecture.eco
  
• borland.public.csharpbuilder.modeldrivenarchitectu
  re.eco