SAP Web Dynpro for Java
NWDS-WebDynpro Program
1. Netweaver Development Studio 1.1. Overview The Netweaver Development Studio is a SAP extension of the open-source Eclipse project. SAP provides additional plug-ins for Eclipse to enhance Eclipse is relation to SAP technology. More or less everything you know from the handling of Eclipse can be applied to the NWDS. To run Web dynpro for Java applications you need the Netweaver application server for Java. To develop these applications you need the SAP Netweaver Development Studio.
1.2. Download SAP Netweaver Composition Environment You find trivial version of the NWDC on the SAP Developer Network. http://sdn.sap.com Select here Downloads. Currently the best download is the SAP Netweaver Composition Environment. Downloading the software requires a valid user. Requistration is free of charge.
2. Webdynpro Introduction 2.1. Overview Webdynpro for Java (Java WD) only runs on the server. You can develop locally with the SAP Netweaver Development Studio but to test and run the application you have to deploy the application to the server. Java WD runs on the Netweaver application server for Java (NWAS Java) which is decoupled from the SAP ABAP application server. To access the SAP ABAP application server you have to use Remote Function Calls (RFC) or Webservices.
2.2. Component The basic element of WD is the component. Each WD component is a separate Java program. The source for this java program is generated automatically. This source code contains places, so called hooks, to extend the standard coding. Each component contains out of serveral interfaces and controllers. There are several types of controllers •
Component Controller - controls the component
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SAP Web Dynpro for java
SAP Web Dynpro for Java •
NWDS-WebDynpro Program
View Controller - controls the view
In addition to the standard hook methods the programmer can also declare controller instance methods (in the methods tab of the controller) and define the method and its parameters. Also in addition each controller contains at the end of the source code a coding block in which the programmer can put any code and member variables he likes.
2.3. Context Each controller has one hierarchical data storage structure called context . The context is a local memory which allows to store hierarchical data for a specific WD component, e.g. view and / or controller. Each context has a root element. Under that root element the other objects are stored. The context of each component can be connected.
2.4. Development Components If the developer would like to structure his work over several project and / or work distributed on several project he can use "Development Components". Within DC's you can add dependencies via "DC Definition" -> Used DC -> Add Dependency Dependent DC's are available at design time, to make then available at runtime on the server they need to be deployed to the server. Select your DC, right mouse click, select Development Component-> Build. This will make the DC available at design time. Select your DC, right mouse click, select Development Component-> Deploy. This will make the DC available at runtime on the server. Development Components (DC) are normal project which can create via New -> Development Component. DC can define the public API, e.g. which elements are avaiable for other development components. E.g. if you define a structure type in one development component you can add it ot the public API via right mouse click -> Add to public part.
Tip
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SAP Web Dynpro for java
SAP Web Dynpro for Java
NWDS-WebDynpro Program
If you add a structure to the public part then you have also to make the simple types available . Model, e.g. access to external data sources, are usually create as DC.
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SAP Web Dynpro for java