Question:
dear gurus,
i am a student and involved in bw integration project. my role is to develop a concept for integrating my company's java tool to sap bw. i have suggested to use BI JAVA SDK, later i have done lot of research in finding a solution and found that BAPIs and RFCs make easier for my project. i have also gone through the bw third party vendor sites, all the bw connectors & adapters are developed in BAPIs.
i am in big dilema to start my development in moving to java or bapi direction. if any one had already involved in bw integration project plz guide me. ideas from different gurus can share and are appreciated. thanks a lot.
with best regards,
pandu...
Answer:
ABAP(BAPI's) is better in my opinion
ABAP versus Java?
Summary
When SAP brought R/3 to market in the early nineties its architecture was based on three principles: three-tier client server architecture on top of UNIX, use of relational database management systems and application development in a 4GL environment (ABAP/4). The success of this approach was based on the portability of the applications (as ABAP had its own VM, the ABAP processor). The strength of ABAP was its application server features (such as internal tables) and its database access layer (OPEN SQL).
With SAP NetWeaver™, SAP offers a second programming environment based on Java. Java and ABAP have much in common. Both use a VM approach, both have more or less equivalent semantics (e.g. object orientation), yet a very different syntax. Java is accepted as a standard in the industry while ABAP is proprietary and has no relevance beyond the SAP ecosystem. On the other hand, Java does not offer very much help when it comes to database access and application server features. This is left up to additional software layers (J2EE) and is not part of the language.
By SAP AG
26 Apr 2004
When to Use What
In general it is not easy to say what language should be used for what purpose. Different aspects have to be taken into account. In most cases SAP has already developed software layers in ABAP, so you simply cannot start from scratch. Let us briefly look at the different layers a typical SAP application consists of: database access, business logic and user interface.
Database Access
The success of an SAP application depends on its performance and portability. Today, database access written in ABAP is considered to be manageable. A couple of features such as table caching and statement caching have been incorporated in the runtime environment for ABAP. In general you wouldn't be surprised by the performance of an ABAP application. If you follow some well known priniciples for robust and performant ABAP programming your database access layer will prove to be valid.
This is not necessarily the case with Java. Although many of the above ideas have been adopted to the SAP Web Application Server 6.40 (OPEN SQL for Java) many features are not optimized since the SQL does not map perfectly to Java. Java has no concept of internal tables which are highly optimized for the ABAP environment. If you do not take special care of your database access in Java the performance experience will be less impressive than in ABAP. ABAP also makes use of shared resources that are less common in a J2EE environment. Consequently, more copy operations are to be expected in Java.
Application Server Features
Closely related to the database access are the various application server features of ABAP, especially the handling of large data volumes stored in internal tables. Java in contrast does not offer a generic concept in this respect. That means that any scalability issue has to be solved by the Java application programmer.
A second aspect is the OLTP nature of ABAP applications. They are forced to release database resources based on the current dialog status. Again, a similar approach can be implemented in Java. However, this discipline is not mandatory and not enforced by the underlying application server environment. If you look at application server and database access certainly ABAP based applications will prove to be more performant unless you invest a serious amount of coding discipline in your Java projects.
User Interface
When it comes to user interface the battle is more open. From a market perspective all applications should run in a user based portal. SAP has decided to implement its enterprise portal in Java for interoperability reasons. Experience has shown that a former approach using ABAP based technology (Workplace) was not accepted in the market. The SAP Enterprise Portal offers new features such as collaboration, unification and integration of structured and unstructured (knowledge management) content. While the portal is written in Java, the building application blocks (iViews) can be written based on different technologies. Some are written in Java using a tag library called htmlb, some use ABAP based technology called business server pages. The technology used depends on the nature of the iView.
Web Dynpro
To overcome this heterogenous world, SAP invented its Web Dynpro technology. Web Dynpro, as the name suggests, brings in all the experience of the ABAP world (dynpro), but prefers a Java based implementation with powerful tools (SAP NetWeaver™ Developer Studio) based on Eclipse. Web Dynpro leverages the UI design to a model-driven approach where code is added at a very late point it time. This makes Web Dynpro a rather programming language independent technology. In fact Web Dynpro is also available for the ABAP environment, but the ABAP based implementation is primarily designed for the conversion of the tremendous existing code base of the classical dynpro. Please note that Web Dynpro ABAP is not yet released in SAP NetWeaver '04. The reason is quite simple. SAP first wants to gain experience with its own applications before releasing the technology to customers.
Development Infrastructure
When you compare the ABAP and Java environment from a design time perspective you should keep in mind that the ABAP infrastructure (Workbench Organizer, correction and transport system) has evolved over the last ten years while the Java development infrastructure today consists of tools like perforce and a nightly build procedure. To overcome this limitation SAP has invented a repository-based approach for Java development (design time repository) that offers version capabilities and supports the development in a very componentized fashion. Nightly builds can be avoided and are replaced by incremental activation procedures that make changes visible to other team members in a distributed development landscape. The new development infrastructure is currently being rolled out, but it will take time to mature.
Conclusion
Today the Java environment aims to be as complete as the ABAP environment, but some work has to be done to reach the robustness and scalability of the ABAP environment. Java already competes with ABAP in the user interface layer. The rest of an application's stack is still domionated by ABAP. Most likely, we will find mixed scenarios where Java drives the frontend and ABAP dominates the backend. However, this two-language coupling has its price (remoting, state handling) and this is the reason why some applications have decided to implement the frontend also in ABAP where you have less integration problems, but you are less opened up to industry standards such as J2EE. On the other hand, early adopters such as cross app frameworks use the whole Java stack down to the persistence layer. As always, with topics such as ABAP versus Java there is no simple yes/no answer.
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Answer:
(I didn't read the whole thread)
It is a fact that you would find more people able to help you with BAPI than with JAVA, just due to the fact BAPI is a "old"well known way of doing things in SAP.
Ch
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Answer:
A very nice conceptualisation and differentiation between ABAP and Java related environments. A must read by all SAP gurus. Thanks SAP_COHORT for the info..
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Raj
Have a Nice Day:-)
Answer:
dear SAP_COHORT & CHC,
i am lucky and thankfull to both of them. i have read an excellent documentation from sap_cohort its worth and information was very helpful.
i will try to work with BAPIs than java, thanks CHC for ur suggestion. good luck.
pandu