WSDS Client: Bridge to the Web Service
WsDataSourceClient
- provides link to the web service
- uses HTTPS for secure communication
- SOAP requests are authorized
- extends stub generated by JDeveloper
- converts data presentation between ADF and SOAP
EnvInfoProvider
Authorization:
- getUsername()‏
- getPassword()‏
Web service call methods:
- doExecuteQuery()‏
- doExecuteDML()‏
Value conversion:
- formatValue()‏
- parseValue()‏
- convertTypes()‏
- buildDataSet()‏
WSDS Client: Bridge to the Web Service


The client's purpose is to call web service operations on behalf of certain user.

To protect transmitted content during its movement through Internet, secure HTTPS protocol is used.

User credentials are sent in every request. For that, application security provider (EnvInfoProvider) should be available for getting user name and password at runtime.

The class extends the stub generated by JDeveloper from the web service WSDL file. This stub contains all necessary commands for creating SOAP requests, sending them to the web service, and parsing returned responses.

In previous slides we've detected that ADF programmatic mode requires two data source operations for the web service to be a data provider:
- ExecuteQuery (query, params, fetchSize, rangeSize)‏
- ExecuteDML (statement, params)‏

The client has methods to call these web service operations following the rules defined in the web service WSDL file.

Another responsibility is to convert data presentation between ADF and SOAP.
For that, all transmitted values are supplemented with type-indicators, which are well-known for the client and the web service.