1. Component-based Software Engineering Marcello Bonsangue LIACS – Leiden University Fall 2005 Component Model Comparison

2. 02/06/2015Seminarium CBSE2 Commercial Component Models  Open standard CORBA  Microsoft COM/DCOM.Net  SUN JavaBeans Enterprise JavaBeans  Philips,Nokia et al. RoboCop

3. 02/06/2015Seminarium CBSE3 Comparison criteria (I)  Components Abstract components (Interfaces) Concrete components (Implementations)  Basic communication  Composition of components  Adaptation (external and internal)  Reusability / Predefined services

4. 02/06/2015Seminarium CBSE4 Abstract components  Corba Interfaces generated from IDL Multiple inheritance  DCOM Interfaces generated from MIDL Interfaces as first class objects Multiple inheritance Globally unique interfaces  JavaBeans/EJB Defined by EJB designer Multiple inheritance .Net Interfaces generated from concrete components Multiple inheritance

5. 02/06/2015Seminarium CBSE5 Concrete components  Corba classes (objects) With reflection / transaction / persistency concept Language + platform transparency Inheritance of the implementation language  (D)COM objects and Interfaces With reflection / transaction / persistency concept Language transparency Inheritance of the implementation language  JavaBeans, EJB With reflection / transaction / persistency concept Java but JNI Platform transparency Single inheritance of Java Different roles in EJB (stateless, session, entity, message-driven) .Net With reflection / transaction / persistency concept Language (but CLS) + platform transparency Inheritance of the implementation language

6. 02/06/2015Seminarium CBSE6 Basic communication  Corba Object request broker – ORB Remote procedure call (RPC) GIOP/IIOP (General/Internet Inter ORB Protocol)  DCOM Object oriented (RPC) GUID (Globally Unique IDs)  JavaBeans Asynchronous, Event based  EJB EJB container and (web) server Synchronous Remote Method Invocation (RMI) Support for lease-based communication Migration of Java code .Net Synchronous Remote Method Invocation (RMI) Support for lease-based communication

7. 02/06/2015Seminarium CBSE7 Composition of components Category 3 (Koala, RoboCop) Category 1 (JavaBeans,.Net) Category 2 (EJB, COM, CORBA) Category 4 (ADL, UML 2.0)

8. 02/06/2015Seminarium CBSE8 Composition of components  Corba Call via ORB Aggregation with pattern façade (also dynamic)  DCOM Call via (D)COM library Delegation in components using wrappers Aggregation of classes with pattern façade (only static) Aggregation of interfaces  EJB Call via container Java language concepts for delegation .Net Call via CLR Delegation

9. 02/06/2015Seminarium CBSE9 Adaptation  Aspect separation (all) Separation of interfaces and implementation Multiple interfaces per implementation Separation of persistency, transaction, distribution, …  External adaptation Bridges between the worlds  EJB – Corba  Java – DCOM  Corba – DCOM

10. 02/06/2015Seminarium CBSE10 Internal adaptation  Generation of glue code from interface descriptions Corba  Stub-Skeleton generated from IDL DCOM  Proxies and Interfaces generated from MIDL EJB  Proxies generated from bean interfaces  Reflection to adapt dynamically Corba, DCOM EJB.Net

11. 02/06/2015Seminarium CBSE11 Reusability / Services  Corba: standardized general services (Facilities and Services) domain specific services (Vertical Facilities)  DCOM quasi standardized general services Non-standard domain specific services  Microsoft applications  EJB quasi standardized general services quasi standardized domain specific services  AWT and Swing (JavaBeans)  Other Java libraries