Object Oriented Programming in 2014: Standard or Legacy?

Mathieu François@Universitas Bina Nusantara

07/11/2014

Did Object Oriented Dominate Programming?

Introduction1. The Great Hopes About OOP*2. There is no Silver Bullet3. Case: Epigami OO Infrastructure

* Object Oriented Programming

Programming: Art or Science?

Computer Science vs Programming

The Art of Computer Programming

Practices In Real World

Who Studies History In Engineering?

The Great Hopes About OOP

Software?

• Encapsulation• Polymorphism• Inheritance

• Class of objects (constructor)• Instance of class• Method vs data• Message passing• Abstraction

OOP Definition

OOP Hype In The Mid-90s

Why the OOP Cult?

OOP perceived as the solution for all software development challenges:

• Code reuse and recycling• Encapsulation of knowledge• Isolation of bug impacts• Design benefits, especially for very large

programs• Maintenance

Pure languages: Ruby, Python, Smalltalk, Scala, Eiffel

Languages mainly OOP but also have procedural elements: C++, Java, C#, VB.NET

Languages historically procedural but extended with OO features: Pascal, VB, Fortran, Perl, Cobol 2002, PHP

OOP In Almost Every Languages

Profusion Of OOD Solutions

20 Years Later… How Did OOP Succeed?

OOP For Kernel Development?

OOP For Kernel Development

Linux, Windows, OS X… They are still all based on good old-fashioned C

OOP For Web App?

OOP For Web App?

Yes: Languages, DOM, JSON

No: Service Oriented Architecture, Event-Driven Design

More about SOA in a few slides...

There Is No Silver Bullet

There Is No Silver Bullet

By Fred Brooks (1986), also author of TheMythical Man month (1975)

Essential Complexity vs Accidental Complexity

Since ‘modern’ languages (Fortran, COBOL), no real improvement about accidental complexity

org 7C00h jmp short Start ;Jump over the data (the 'short' keyword makes the jmp instruction smaller) Msg: db "Hello World! " EndMsg: Start: mov bx, 000Fh ;Page 0, colour attribute 15 (white) for the int 10 calls below mov cx, 1 ;We will want to write 1 character xor dx, dx ;Start at top left corner mov ds, dx ;Ensure ds = 0 (to let us load the message) cld ;Ensure direction flag is cleared (for LODSB) Print: mov si, Msg ;Loads the address of the first byte of the message, 7C02h in this case ;PC BIOS Interrupt 10 Subfunction 2 - Set cursor position ;AH = 2 Char: mov ah, 2 ;BH = page, DH = row, DL = column int 10h lodsb ;Load a byte of the message into AL. ;Remember that DS is 0 and SI holds the ;offset of one of the bytes of the message. ;PC BIOS Interrupt 10 Subfunction 9 - Write character and colour ;AH = 9 mov ah, 9 ;BH = page, AL = character, BL = attribute, CX = character count int 10h inc dl ;Advance cursor cmp dl, 80 ;Wrap around edge of screen if necessary jne Skip xor dl, dl inc dh cmp dh, 25 ;Wrap around bottom of screen if necessary jne Skip xor dh, dh Skip: cmp si, EndMsg ;If we're not at end of message, jne Char ;continue loading characters jmp Print ;otherwise restart from the beginning of the message times 0200h - 2 - ($ - $$) db 0 ;Zerofill up to 510 bytes dw 0AA55h ;Boot Sector signature ;OPTIONAL: ;To zerofill up to the size of a standard 1.44MB, 3.5" floppy disk ;times 1474560 - ($ - $$) db 0

OOD Is Not the Only Design Approach

Other Approaches or ‘Schools Of Thought’:• Functional• Event-driven• Data-driven• ‘Unix Philosophy’

Object-Relational Impedance

We use Object Relation Mapping (ORM) because Object DBs didn’t really take off

“organizations which design systems ... are constrained to produce designs which are copies of the communication structures of these organizations”

Bad collaboration or project management have not solved by OOP

Conway’s Law Still Applies to OOP

Conway’s Law Illustrated

But The Main, Main Failure Of OOP Is...

CORBA, DCOM fundamental flaw was to assume Location Transparency

Local vs Distributed Objects

Network Is Not Transparent

Welcome to the REST API Web (Economy)

From OOA to SOA

Case: Epigami OO Architecture

Why Not Apply OOD To Our Infrastructure?

Infrastructure Since 15 years

• Hardware Technologies +++

• Virtualization Technologies +++

• System Configuration Management +

‘Infrastructure As A Code’: Really?

First deployment automation in the 90s (Jumpstart SUN & Co)

Puppet & Chef are just improved automation, not a new real paradigm

Light virtualization based on containers

From Infrastructure to Application-centric

The New Kid On The Block: Docker

Docker In A Nutshell

Infrastructure ‘Code’ Lifecycle

Infrastructure ‘Code’ Lifecycle

If Infrastructure is Code, why not use OOD?

OOD Applied to Docker

Docker

Image BuildRunning Container

‘Jailed’ ProcessFROM <image>

Init ScriptEXPOSE <service>

Container LinkLink Alias

Object-Oriented

ClassInstance of ClassEncapsulationInheritanceConstructorMethodMessage PassingAbstraction

Infrastructure Object Hierarchy

Benefits

• Isolation• Security• Modularity• Traceability• Automation (Continuous Deployment)• Flexibility• Performance• Scalability• Price

Summary

• Pros & Cons of OOD

• There is no Silver Bullet

• Continuous Evolution of the design paradigms, built on top of the previous ones