1	"PeopleSoft Application Classes - Easing..." PeopleSoft Application Classes - Easing the Path to Fusion
2	Me Simon Huggins PeopleSoft Consultant at nee Allinity Now Compel Business Solutions [ STAND 47-48 ] Part of Compel [ Free Roulette! ] Part of 2e2 So I am an instance of employee class called “consultant”. 2e2 is Parent Class, Compel is SubClass, Compel Business Solutions Sub-SubClass
3	"Application Classes have been available..." Application Classes have been available for a while now as an alternative to function libraries in PeopleTools. The object-oriented thinking that embodies this technology can be seen as the road forwards to the final Fusion development architecture. This seminar gives some real-life examples of how to use Application Classes as a framework for your business logic, and goes through some of the pros and cons for Designers, Programmers and Managers. It also shows examples of how this technology is actively employed within PeopleSoft Application and Portal technology. It argues the advantages of reusable and extensible coding, and that it is a mid-path shift in mindset that will ease the eventual change from PeopleCode to Java, and make the transition from PeopleCode to class-based Java far more intuitive, thus minimising the transitional learning curve and business impact of developer retraining. Time to get object oriented.
4	Fusion and App Development Fusion Architecture here now Applications will be Java-based Development using JDeveloper Might be an idea to investigate Oracle Apps… … As JDeveloper now replacing Forms development Java is Object Oriented – Class based Application classes exist in PeopleSoft
5	Fusion Upgrades First Oracle Apps due in the next few years No guarantee of porting of PeopleCode “Apps Unlimited” says we will all be supported for a good long time… … But this is a bit hazy on supported platforms when you look at your contracts - what when these go out of date? May be looking at a rewrite of PeopleSoft business logic in Java
6	Case for “Skilling Up” PeopleSoft traditionally event-based Triggers from limited set of objects – e.g. records, components, messages Java class based. Events are class “Methods”. PeopleSoft Application Classes can model this Classes are based on real-life entities – so can map better to business processes Use classes now, developers have most of the skills required to develop in Java When porting, easier to map classes-to-classes
7	Potential Issues The Object Model for Fusion is not yet available. Difficult to know how to accurately model classes If you don’t skill up now, it’s a steeper learning curve when Fusion arrives Replace existing Function Libraries or Introduce Application Classes / Packages with new implementations? More work associated with creating App Classes than creating a quick one-off function
8	Case for implementing class-based business model No idea of structure to be used in Fusion If to be class based, create classes for business objects now in PeopleSoft Reuse and extend classes for future projects When need to upgrade, could potentially keep much of existing class hierarchy and map this to Oracle classes using transformational classes Or reimplement the business model at lower class levels in terms of Fusion access model
9	Case against implementing class-based business model Extra training-up (even if informal) Debugging is more complex / haphazard – e.g. watching variables can be temperamental Complex hierarchies can be difficult to follow / maintain as the business logic can be over-abstracted Function Libraries are known and loved (!?) Code looks more complex More difficult to optimise database access due to abstraction from entity to business model
10	Object Orientation Wikipedia Definition:- Object-oriented programming (OOP) is a programming paradigm that uses "objects" and their interactions to design applications and computer programs. It is based on several techniques, including inheritance, modularity, polymorphism, and encapsulation.
11	Classes & Plato Plato invented these really – believed that every object was stamped from an idealised “form” – e.g. an idealised form a human exists which we all mimic. This form are archetypes of many types & properties. A “Class” (or Plato’s “Type”) represents an idealised, pared-down view of an object in reality – e.g. a “Human” Application Classes are PeopleSoft’s implementation of a “Class”
12	Prize Question Plato, they say, could stick it away…. … How much every day?
13	Objects Sometimes “Object” used when mean “Class”. Careful! Object is an example (or “instance”) of a class – e.g. if have a class called “Human” Jim is an object of class human with yellow hair and dodgy clothes and job: DBA Hema is an object of class human with black hair amazing clothes and job: HR Person Objects are created, instantiated (i.e. given an initial state), used/abused, and destroyed (often automatically according to scope)
14	Example Class of Human PeopleSoft Class Human method Human(); property string hair; property string clothes; property string job; End-Class;
15	Properties or Attributes Property (or attribute or message) can be seen in various different ways:- A measurable property of an object – e.g. hair colour A part of an object’s state (i.e. the property is maintained during the life of the object) A way of defining how data goes into and out of an object (i.e. an interfacing method – hence message) A variable with specific scope (not strictly true, but the nearest programmatic analogy) A property has a type – often that type is another Class (e.g. job: class of AllowedJobs)
16	Inheritance Class: “Human” Subclass “Employee” Has properties of Human (i.e. Hair Colour, Job etc.) Thus “inherits” properties of “Human” class Has extra properties such as “Pay Reference” and “Department” – so “extends” the “Human” class Application classes allow for base abstract classes (as does Java) – which means at “Human” level we may declare that (e.g. Hair Colour) must be specified in subclasses, but not define how. Implemented in “Employee”
17	Sample of subclassing PeopleSoft Class Human method Human(); property string hair; property string clothes; property string job; End-Class;
18	Methods Properties define the interface to the “state” of an object. Methods are the functional “engine” of an object – the doing bit that changes the “state” of an object and retrieves info about that state. In Application Classes, can define a property dynamically by defining its input and output using “set” and “get” methods.
19	Example of “Get” and “Set” class Human method Human(); property string Hair get set; private instance string &myHair; end-class;
20	Polymorphism Create a “Human” class Create an object of type “Human” Write some code using Human objects Create a subclass of “Human” called “Employee” Add some code to change the object code is working on to “Employee”. Code stays the same, but now working from “Employee” object “Knows” which object to use based on what object Can only use methods/properties from “Human” Use Downcasting for methods etc. from “Employee”
21	… And The Rest There’s a lot more – for example:- Application Packages hold application classes – i.e. a sort of class library Multiple inheritance (e.g. where a class has more than one parent) is not supported Encapsulation – i.e. scope of properties and method within objects Abstraction – i.e. hiding details of lower levels in a class hierarchy by generalising at higher levels You can use Java from within PeopleSoft – it’s a bit clunky, bit can be done
22	PeopleTools 8.48 Web Service Integration Services and Service Operations Services Component: create and manage services. Service Operations Component: create and manage service operations (creating operations, assigning messages, adding handlers, etc.) Integration PeopleCode Extend delivered application classes to create messaging logic. Logic is attached to handlers instead of messages. New object called IntBroker with many of the methods and functions of the Message object Provide/Consume Web Services
23	PeopleSoft Enterprise Talent Acquisition Manager Framework
24	CDM (CRM) Business Object Relationship Model (BORM)
25	CDM Application Class Hierarchy
26	CDM Customization Chris Collins – 2004 Customization – CRM Site Component E.g. New Site Class extending PS Site class
27	Portal No Portal Examples – Sorry! Portal is class-based Can do some sneaky “customisations” by playing with these classes. Careful! These changes will inevitably be unsupported. Investigate by all means – look in app packages – e.g. PT_NAV / PT_BRANDING (v. interesting to customise!!!) When tracing through code – you’ll inevitably stumble across these classes
28	Excel Reporting Library Create Base Excel reporting Class Worksheet Class Instatantiate using Run Control & Data Record Source Multiple Worksheets can be instantiated from different sources Row class, Column class etc. to define spreadsheet (either automatically from data structure or programatically) Generate Excel report using XML schema in potentially 4 lines
29	Links Basic Java Course: http://simonhuggins.com/courses/javaweb Presentation not posted on UKOUG web site yet – will post shortly. Will also post presentation + sample project as Change Package on http://ww.simonhuggins.com/peoplesoft/UKOUG/2007 ASAP May even give instructions on how to extract the project to avoid using Change Assistant (bleugh!) http://www.compelbs.co.uk – Compel Business Solutions
30	Thanks to… Andrew Terrell (pointer to CRM & CDM Red Paper) Chris Collins (Sample of Inheritance & Casting to prevent customisation) (Dr) Dave Gaff & Manish Patel (overviews of Application Messaging) My Wife My Agent (!?) My Cat etc etc. blub blub.