1. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie Component Technology objects versus components -- definitions interoperability requirements for distribution a simple workgroup application extending hush with CORBA Additional keywords and phrases: (D)COM, Java, CORBA, OLE, persistent objects, ODMG, workgroup

2. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie Objects versus components Subsections: Definitions The technology matrix Component myths

3. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie Definitions Component substitutability unit of independent deployment unit of third party composition no persistent state Object identity unit of instantiation (persistent) state encapsulation of state and behavior

4. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie A software component is a unit of composition with contractually specified interfaces and explicit context dependencies only. A software component can be deployed independently and is subject to composition by third parties. Szyperski

5. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie The technology matrix distribution mobility language platform reflection COM - - * - +/- DCOM + - * +/- +/- CORBA + - * * +/- Java/Beans - classes Java * + Java/RMI + classes Java * + Voyager + objects Java * +

6. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie Components: Myths and Reality component-ware allows for combining components if semantical issues can be resolved component-ware simplifies software distribution and maintenance development becomes more complex component-ware support mega applications it affects performance significantly component-ware is a revolution wrong, it is an evolution from OO and C/S unknown source

7. vrije Universiteit amsterdamPostacademische Cursus Informatie Technologie Component Questions How to describe the interaction between components? How to manage variety and flexibility? How to guarantee critical system-wide properties?