1. RMI CORBA Matt

2. 2 RMI VS CORBA

3. 3

4. 4 J2EE

5. 5 Sample Application

6. 6

7. 7 RMI-IIOP

8. 8 Tools New rmic compiler  Converts Java Interfaces to IDL  Generates IIOP Stubs and tie classes New idlj compiler  Maps IDL to Java  Generates IIOP Stubs and tie classes

9. 9 RMI to RMI-IIOP IIOP RMI Java Client RMI Java Server tie class rmic -iiop Complier stub class RMI Implementation

10. 10 RMI to RMI-IIOP 1.Converting Server Extend your implementation class from PortableRemoteObject rather than UnicastRemoteObject: Use JNDI naming service rather than rmiregistry. 2.Converting Client Use JNDI naming service to locate object Use PortableRemoteObject.narrow() method rather than Java type cast.

11. 11 IDL to RMI-IIOP Write Java IDL Use idlj compiler  Generates Java Mappings  Generates stubs and skeletons Implement Server Run Server and register with JNDI service Develop Client and test

12. 12 RMI-IIOP With RMI and CORBA, programmers face a cruel choice: they must decide between RMI, with its easy programming features, and CORBA, with its broad interoperability. With RMI-IIOP, programmers can create applications in RMI that include CORBA connections RMI over IIOP (RMI-IIOP hereafter), developed jointly by IBM and Sun, is a new version of RMI (Remote Method Invocation) for IIOP (Internet Inter-ORB Protocol) that combines RMI's easy programming features with CORBA's interoperability. RMI and CORBA have developed independently as distributed-objects programming models. RMI, a foundation of the EJB and Jini technologies, was introduced as a Java-based, easy-to-use programming model for distributed objects. CORBA (the Common Object Request Broker Architecture), defined by the OMG (Object Management Group), is a well-known distributed-object programming model that supports a number of languages. The IIOP protocol connects CORBA products from different vendors, ensuring interoperability among them. RMI-IIOP is, in a sense, a marriage of RMI and CORBA.

13. 13 RMI-IIOP 與 J2EE 1.3 相容的 server 都有 RMI-IIOP 實作功能， 可以協助處理各種網路問題

14. 14 Before RMI-IIOP

15. 15 It used to be difficult to choose between RMI (JRMP) and CORBA when starting a new project. If you selected RMI (JRMP), you got easy programming, but lost interoperability across multiple languages. If you selected CORBA, you got interoperability, but faced a more daunting programming task. Please connect the two

16. 16 Java RMI clients can access RMI/IIOP objects through ordinary RMI interfaces. CORBA clients need equivalent interfaces in IDL.

17. 17 Java RMI clients can access RMI/IIOP objects implemented as CORBA objects through ordinary RMI interfaces. CORBA clients and RMI/IIOP object implementations need equivalent interfaces in IDL.

18. 18 Example of interoperability scenario between different vendors of EJB containers.

19. 19 RMI/IIOP architecture.

20. 20 RMI

21. 21 RMI Architecture

22. 22

23. 23 Java IDL

24. 24

25. 25 CORBA

26. 26 CORBA CORBA (Common Object Request Broker Architecture) 是在 1992 年由 OMG(Open Management Group) 組織提出的。那時的分佈式應用環境都採用 Client/Server 架構， CORBA 的應用很大程度的提高了分佈式應用軟體的開發效率。 CORBA 的 IDL 採用類 C++ 的定義，是公開的規範 IIOP 是 Internet CORBA 互換性的通訊協定 Object Request Broker (ORB) 是 CORBA 之間網路傳遞的基礎， ORB 負責找到 服務方法的物件，負責處理參數傳遞與傳回結果

27. 27 CORBA IDL 用來發展與整合 CORBA 物件的服務， IDL 是一個可攜型的 規格語言。使用 IDL 編譯器可以產生前面所提到的 Stub 和 Skeleton 程式碼，並且可以對應許多高階程式語言（如： Java 、 Smalltalk 、 C++ 等等） 有了 IDL ， CORBA 應用程式可以是由不同程式語言撰寫的 IDL 與 Java 結合