02/10/2015 Page 1 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Ervaring CBD

02/10/2015 Page 2 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Main software production accents  Quality  Effort  Turn-around time

02/10/2015 Page 3 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Summary Software Development Methods 25-30% Procedural (structured) OO Components CORBA Java Beans COM/OLE/ActiveX Own Approach

02/10/2015 Page 4 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Software Engineering and Production BOS - Business Opportunity Scanning Analysis Phase Design Phase Implementation Phase Integration Test Phase System Test Phase Design Maintenance Requirements definition independent of development method 10 … 1000 designers ISO Individual phases filled

02/10/2015 Page 5 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments (Traditional) Procedural development  Use of SDL/CHILL ( years experience), C and assembler structured - modular evolving (OO flavours)  very well described development & quality rules  Full set of Siemens tools CM, error tracking development tools, compilers debugging tools  Siemens OS, software frameworks, hardware platforms  Most projects are “Huge projects” ( MY)  Relative long turn around times per software release  High quality  Known risks

02/10/2015 Page 6 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Object Oriented Methodology  Mid eighties we assumed OO reduces turn-around development time OO improves reusability OO improves quality OO improves testability OO improves management of complexity OO offers better tools  In general we thought that: OO is the ideal methodology for small, medium, large projects allowing a fast response to the market.

02/10/2015 Page 7 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments OO experience/1  Smaller turn-around times: we do not know training (modelling, coding, tools) object modelling (not that simple) we measured shorter coding times we do not measure an improvement of correctness  Reusability less redundant code within the project only a fraction of the code (< 10%) can be reused by other projects (lack of a generic approach, concept, framework)  Management of complexity Better anticipation of complex requirements Better software structuring (improved adaptability, patterns) But beware for “aesthetic” (coding) complexity and poetic freedoms

02/10/2015 Page 8 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments OO experience/2  Quality source code reuse is limited OO/OOP enables to realise software products of increasing complexity but with the same quality expectations. Quality is largely independent of the programming language ex. first release of software product: l C - implementation: 2.4 errors/1000 LOCS l C++ - implementation: 2.9 errors/1000 LOCS source: datanews,  Improved testability correct: improved and simplified methods but : OO does not necessarily guaranties correctness and compliance of imposed requirements.  Tools: ??? Training, type of project, constraints, limitations, complexity, user interface, ….

02/10/2015 Page 9 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments OO experience: conclusions by consensus  OO is NOT a revolution. As such it does not free you from traditional development, management and quality problems. Neither does it ensure a faster turn-around time.  OOP as part of OO offers a substantial number of benefits but only covers the aspects “programming” and “testing”. Abstraction, encapsulation inheritance polymorphism (dynamic binding) patterns  Moving towards OO development requires an extensive amount of training and coaching  The main reason to advocate OO is the fact that OO enables you to challenge complex software systems, in a more conforming way than traditional methodologies

02/10/2015 Page 10 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Improving development turn-around time and quality  Improvements turn-around time, cost and quality are limited despite of methodology despite of improved training of the design team despite of tools  But can possibly be improved by reuse of existing and well-proven source code usage of existing and well-proven binaries I.e. components

02/10/2015 Page 11 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Component definition Is an encapsulated piece of code (source or binary) which complies with a well defined and known set of generic and specific rules and functions.  Generic rules/functions refer to the need for a “framework” initialisation configuration monitoring exception handling interworking with other components persistency real time behaviour memory utilisation portability  Specific rules refer to the expected behaviour

02/10/2015 Page 12 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Experience : commercial software packages/1  Specific functions : OK we save time: we don’t have to worry about specifications and standards but : we need time for evaluation and selection  Quality : OK correctness: good interoperability: good  Framework no standardisation (vendor specific) training is needed a lot of glue code is needed portability depends on a limited number of operating systems a lot of time is needed to get the packages up and running

02/10/2015 Page 13 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Experience : commercial software packages/2  Effort gain (at medium to long term) design maintenance rich(er) feature palette from the beginning synchronisation with evolving standardisation (including de-facto standards)  Turn-around time to get first release up and running may not be under-estimated l environment aspects not covered by the package l lack of a standard framework but you will save time at medium to long term  Main risks vendor stops supports the product vendor redesigns the basic concept

02/10/2015 Page 14 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Experience: component frameworks  Non real time applications CORBA l application for multi-level service integration for large networks l small turn-around time and a complex multi-hosted application (limited : activeX, beans)  real time applications no commercial approach use of own-defined frameworks (limitations) l based on experience: set of rules, patterns, code, tools l improved portability and reuse of software (within product gamma) l improved integration turn-around time l improved testability

02/10/2015 Page 15 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Experience with own defined frameworks  A lot of time and effort is needed to realise a stable specification  Acceptance is not obvious  Training is required  Impact on performance  But once accepted better focus on the requirements improved work-split improved off-line testability improved integration  We expect improved robustness less design maintenance

02/10/2015 Page 16 R. Theeuws Siemens Atea Filename: CBD_ervaring Werkgroep Component Based Developments Advocating a standard framework  High quality software component specialisation application specialisation  Lower application specialisation turn-around time reuse of standard components de-coupling between component and application  At long term : lower development effort