SAP Netweaver Interview Questions
Equity Press
Compiled by Craig Gutjahr
SAP Netweaver Interview Questions
ISBN: 978-1-60332-310-9
Smashwords Edition
Edited By: Jamie Fisher
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Netweaver Portal – The SAP Netweaver Portal is the default user interface for web-based applications. It is the component of Netweaver which handles the user’s interaction with the applications
Exchange Infrastructure - Exchange Infrastructure is SAP’s enterprise application integration software. It is a component of Netweaver product group that is used to enable exchanges of information among systems, internal software, and external groups.
SAP Master Data Management - Master Data Management supports information integrity throughout the business network in a diverse IT environment. It ensures cross-system data stability and facilitates the sharing of master data.
Mobile Infrastructure - Mobile Infrastructure delivers multi-channel access to enable connection to enterprise systems through mobile, voice, or radio-frequency technology.
SAP Netweaver Platform
SAP .Net Connector
SAP Netweaver Administrator
SAP Web Application Server
SAP NetWeaver is an application builder platform from SAP for integrating business processes across various systems, databases and sources. It is the technological foundation for all SAP products since the SAP Business Suite. SAP NetWeaver is marketed as a service-oriented application and integration platform (i.e. SAP NetWeaver is the interface between SAP applications and is also their runtime environment). It furthermore interoperates with and can be extended using various technologies, some of which are Microsoft .NET, Sun Java EE, and IBM WebSphere. SAP is fostering relationships with system integrators and technology providers, many of the latter becoming "Powered by SAP Netweaver". The strong momentum illustrates the power SAP holds over the market for packaged software solutions.
SAP Netweaver can be seen as part of SAP's plan to transition to a new architecture. From a technical point of view, one can say that SAP NetWeaver is an evolution of mySAP technology, also known as simply SAP.
Composition
Netweaver is a stack of SAP products which are provided under a single license to an Enterprise. Except for mySAP ERP, SAP's flagship product, all the other major business applications from SAP are included in Netweaver. The release of Netweaver is considered as a strategic move by SAP for driving enterprises to run their business in a single platform, i.e. SAP.
Netweaver includes a group of relatively independent Business applications running from a single technical platform, SAP Web Application Server (Web AS).
The lists of products are:
SAP Exchange Infrastructure (XI)
SAP Mobile Infrastructure (MI)
SAP Business Information Warehouse (BW)
What's new:
Interoperability with Java EE (WebSphere)
Interoperability with .NET (Microsoft)
Integration of Business IntelligencexApps
Source: http://en.wikipedia.org/wiki/Netweaver
Source: http://www.netweavercentral.com
SAP Netweaver Web Application Server
Question 01: Web Application Server Technologies
I am a basis consultant who is responsible for installing multiple SAP applications. Most of my applications require the SAP ‘Web Application Server’ but some are Java and some are ABAP, do I install them on the same instance?
A: The SAP Web Application Server you can implement both server-based ( Web ) and client-based (SAPGUI).
Depending on the system requirements, a single WAS installation can run ABAP and/or Java programs. Developers can develop web applications using either ABAP-based BSP (Business Server Pages) or Java-based applications (Servlets, JSPs ect).
There are several different ways the WAS can be installed.
SAP Web Application Server – ABAP
SAP Web Application Server - Java
SAP Web Application Server ABAP+Java
Web Application Server Components
The Internet Communication Manager (ICM) - processes both Web requests. It supports the protocols HTTP, HTTPS, and SMTP.
Dispatcher - distributes the requests to the work processes. If all the processes are occupied the requests are stored in the dispatcher queue.
ABAP Work Process - executes the ABAP code.
SAP Gateway - allows the RFC interface between the SAP instances to be available (within an SAP System and beyond system boundaries).
Message Server - exchanges messages and balances the load in the SAP System.
Java component of the SAP Web AS - Contains the components Java Dispatcher, Server Process and Software Deployment Manager (SDM)
Question 02: W A S Java Standards Support
What open standards are supported by the SAP WAS – Java?
A: Historically, SAP has sat on the sidelines and waited until standards have become supported industry-wide until they fully supported them.
The most recent release of the Web Application Server ( WAS Java Enterprise Edition 5 ) is a departure from that strategy. With this release SAP has almost become an early adopter in the standards.
Here are some details on WAS Java Enterprise Edition 5’s support of standards:
Web Services
JSR 109: Implementing Enterprise Web Services
Java API for XML-Based Web Services (JAX-WS) 2.0
JST 101: Java API for XML-Based RPC (JAX-RPC) 1.1
JSR 222: Java Architecture for XML Binding (JAXB) 2.0
JSR 67: SOAP with Attachments API for Java (SAAJ)
JSR: 173: Streaming API for XML
JSR 181: Web Services Metadata for the Java Platform
Web Application Technologies
JSR 154: Java Servlet 2.5
JSR 252: JavaServer Faces 1.2
JSR 245: JavaServer Pages 2.1
JSR 52: JavaServer Pages Standard Tag Library
Enterprise Application Technologies
JSR 220: Enterprise JavaBeans 3.0
JSR 112: J2EE Connector Architecture 1.5
JSR 250: Common Annotations for the Java Platform
JSR 914: Java Message Service API
JSR 220: Java Persistence API
JSR 907: Java Transaction API (JTA)
JSR 925: JavaBeans Activation Framework (JAF) 1.1
JSR 919 JavaMail
Management and Security Technologies
JSR 88: J2EE Application Deployment
JSR 77 J2EE Management
JSR 115: Java Authorization Contract for Containers
For more information please refer to the Java Enterprise Edition site: http://www.java.sun.com
Question 03: Web Application Server Java or ABAP?
We are considering developing a new custom web-based application utilizing the SAP WAS. Which development platform should we use? ABAP or Java?
A: This is a question that really doesn’t have a clear cut answer. There are many pros and cons for both technologies and SAP really has not produced a clear direction statement as to which direction they will be going with their new products.
Java Overview
The Java program language and environment was designed to solve a number of problems in modern programming practice. The language takes advantage of modern development strategies including:
Object Oriented
Security Driven
Architectural / Platform Neutral
Interpreted
Multi-Threaded
The Java development community began based around ideals of open-standards and community based developments. Overtime companies have taken advantage of the openness and acceptance of the architecture and developed products and development platforms around the Java architecture
Notable Considerations
The following points could be used to make a decision to standardize on the Java development framework
With the release of the WebDynPro for Java and the JEE 5.0 Web Application Server, SAP has shown clear commitment to the Java platform
SAP-specific skills are secondary and there is a considerable amount of Java skilled resources in the marketplace.
Java is inherently architecture and platform neutral. In most cases, code written in Java will run on different platforms with no requirements for portability.
Java has become a mature web-development tool. Frameworks ( Struts etc. ) have been developed to enhance and speed up development of large scale web applications. SAP’s adherence to the Java standard allow for these re-usable frameworks to be integrated into the portal application
ABAP (Web Development) Overview
ABAP originated from an assembler macro language for reporting purposes in the seventies. It evolved to an interpreted language for reporting and dialog programming in the mid-eighties, with compiler and VM implemented in mainframe assembler as part of the SAP R/2 system.
ABAP supports a hybrid programming model. You can use an pseudo object-oriented "OO" programming model based on classes and interfaces, and you can use the more classic procedural and event-driven programming model based on function modules, subroutines, dialog modules, and event blocks.
Historically ABAP is the core development platform for SAP’s client-server based applications and has adopted a web development framework for development of web applications
Notable Considerations
The following points could be used to make a decision to standardize on the ABAP web development framework:
SAP has re-iterated its support of ABAP as a web-development platform with the release of the WebDynPro-ABAP.
There are multiple methodologies for developing ABAP-based web applications, including Mini-Apps
ITS interpreted R3 Screen
Business Server Pages ( BSP )
Scaling of ABAP-based web applications are done in the same fashion as scaling a non-web R3 based application.
Typically the web components of mySAP Applications ( i.e. CRM ) are hosted on the same servers as the historical client-server instances.
For example, the People-Centric UI included in CRM runs on the same servers are the CRM application. Therefore, web components are not abstracted from the CRM application
Question 04: MVC pattern implemented in SAP
Why is the MVC pattern used in SAP?
How do we implement it and what is the logic behind it?
Is there an example?
A: The Model View Controller (MVC) design pattern contains a clear distinction between processing control, data model, and displaying the data in the interface. These three areas are formally distinguished from each other by three objects namely model, view, and controller. As a result, you can easily split Web applications into logical units.
The model is used as an application object of the application data administration. It responds to information requests about its status, which usually come from the view, as well as to statements for status changes, which are usually sent by the controller. In this way, only the model is used to process the data internally, without making reference to the application and its user interface. There can be different views for a model, which can be implemented using different view pages.
The view handles the graphical and textual output at the interface and therefore represents the input and output data in each interface element, such as pushbuttons, menus, dialog boxes and so on. The view takes of visualization. To visualize the status, the view queries the model, or the model informs the view about possible status changes.
The controller interprets and monitors the data that is input by the user using the mouse and the keyboard, causing the model or the view later to change if necessary. Input data is forwarded and changes to the model data are initiated.
The
controller uses the model methods to change the internal status, and
then informs the view about this. This is how the controller
determines reactions to the user input and controls processing.
The
view and the controller together form the user interface.
Since the model does not recognize either views or the controller, internal data processing is detached from the user interface. As a result, changes to the user interface have no effect on internal data processing and the data structure.
You also have the option, however, of displaying the data in different formats. You can display election results as a table, a bar, chart, or as a pie chart.
You can find additional information about the MVC design pattern on the internet and in current specialist literature.
Question 05: WebGui vs ITS report
I have to publish some reports on the Internet. My idea is to write these ABAP reports and to publish them via ITS using the form “WWW_GET_REPORT”.
A consultant said to me that it would be easier to create the ABAP report and use a WebGui. In this, the report would also be more beautiful to see and to use.
Which is the best way to obtain a good layout? Is there any security problem in one of the two solutions?
A: You have to consider the options for the two. If you use the RFC method available through the ITS, you can customize the look and feel of your selection screen as much as you like. You can also create hyperlinks that are underlined in your report.
There is a webRFC example at http://www.sapgenie.com/its/webrfc.htm with the hyperlink showing. As quoted from that site:
With webgui, you get what you would see in SAP. If that's okay, it's the best way to go. The first option is no longer available through the integrated ITS of the WAS, so it would be a short term option anyway.
Does the WAS that comes with 4.7 to replace the need for the ITS?
It seems to me that writing R/3 applications destined for an internet browser are much more easily done with BSP's rather than using the old ITS. If this is the case, what role does the ITS have? Will SAP be dropping it?
A: In most cases the answer is "Sort of". The WAS layer has replaced most of the ITS components and packages with an integrated version of ITS. So ITS is no longer a standalone application.
However, there are exceptions. I know that SRM 3.0 and CRM 4.0 still need ITS instances for IPC. The mySAP Business Suite Web Middleware Installation guide shows ITS used for TREX and IPC, both products which have not been replaced by WAS. SAP has just released the 6.40 Server Components 6.40 CD, which is actually 6.20 SP9. So, I don't think the product will be going away anytime soon.
But you no longer need an ITS installation for BEx, etc. That functionality has not been replaced by WAS and can be activated or deactivated via SICF.
Question 07: Netweaver Portal Platform
I am new to the Netweaver Portal and I need to know the main reasons why SAP customers implement the portal and what benefits it brings them.
A: The SAP Netweaver Portal solution provides users with centralized, easy-to-use access to all the information, applications, and services they need to participate in collaborative business processes. Both SAP and non-SAP applications integrate into the Netweaver Portal.
To create a truly effective portal, it must incorporate all information sources and allow them to interact. But portal content can be much more than general information. With the enterprise portal, users can access content that is targeted specifically to the role they play in their organization. That role may be an external role, such as a supplier or customer, or it may be an internal role, such as a manager or sales agent. For each role, the relevant content comprises a portal application.
Question 08: Portal Performance
I just finished the installation and configuration of the portal according to the needs of the business. How do I determine if the hardware/architecture can handle the load users will put onto the portal?
A: Typically, before a portal is ready to go live, a series of performance or load tests are conducted.
Load tests are used to analyze the entire portal application under a series of realistic, end-user workload scenarios that may last several hours or several days. These tests are usually performed in a production-like staging ( QA ) environment. The results are used to answer questions like:
Are there functional errors that only occur under load conditions?
Why system capacity is needed across all tiers ( Portal, SAP Application Servers ect)
Will the application meet the defined service level agreements?
Is the portal tuned for optimal performance?
Has any recently applied fixes/patches caused negative performance?
Is the application ready for full deployment?
There are a number of different strategies portal customers use for load testing. The following are some examples:
Manual load testing
Open-source load testing tools
Testing frameworks integrated into IDEs
Web-only load testing tools
Several major load testing applications include:
Mercury LoadRunner (www.mercury.com )
Borland SilkPerformer (www.borland.com )
OpenSTA ( Open Source ) (www.opensta.org )
Question 09: Portal Development
I need to begin developing custom content ( iViews ) to run in the portal. How do I get started and what are my options?
A: There are currently several different methods for developing content in the portal. Each has its own benefits and pitfalls.
Web Dynpro
Web Dynpro is a runtime and development environment for creating adaptable web-based applications. The Web Dynpro programming model provides a graphical design tool that allow the development of the UI independently of the underlying runtime platform.
Web Dynpro provides provides a separation of duties when designing a new web application. A business analyst would be able to design a process flow within the Visual Composer. A majority of the underlying code would be developed automatically and a technical resource would be utilized to finalize the development utilizing the Netweaver Developers Studio
The runtime coding will be generated for all platforms, Java and ABAP.
Business Server Pages (BSP)
The "Business Server Pages" (BSP) programming model is the server side scripting technology of the legacy SAP Web Application Server.
Since these applications run natively on the ABAP-based Web Application server, there are advantages when existing SAP logic, data structures and interfaces need to be implemented in a "native" Web application.
A BSP page usually consists of HTML text which includes ABAP as a server side scripting code in special tags. The scripting code allows direct to access to all elements (function modules, database tables, ABAP objects, and so on) in the application server
HTMLB and Java Server Pages (JSP)
JavaServer Pages (JSP) technology and SAP’s HTMLB tool-kit allows web developers and designers to rapidly develop and easily maintain, information-rich, dynamic web pages that leverage existing business systems.
As part of the J2EE family, JSP technology enables rapid development of web-based applications that are platform independent. JavaServer Pages technology separates the user interface from content generation enabling designers to change the overall page layout without altering the underlying dynamic content.
SAP’s HTMLB ( HTML for Business ) provides Java developers a rudimentary Model-view-controller and User-interface tool-kit to assist in developing custom Java-SAP applications
What is the difference between portal roles and R3 roles? How does portal content integrate into a portal role?
A: It is important to note that Portal Roles and R3 Roles are completely different. Their only similarity is that they define what a user sees within their unique applications.