Operating Systems: i5/OS
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Create stateful Web services using the Web Services Resource Framework
You can implement a stateful Web service as a WS-Resource, and
reference it using a WS-Addressing endpoint reference. You develop WS-Resources
in the same way as ordinary Web services using the same tools, however, you
must perform some additional tasks, as described in this topic.
Overview
Perform this task when you want to create a WS-Resource, which
is a combination of a stateful resource and a Web service through which the
resource is accessed. To complete this task have knowledge of standard
Web services development tasks, and the Web Services Resource Framework (WSRF)
specifications. For an introduction to the WSRF specifications, read the OASIS
WSRF Primer document.
Procedure
- Identify or create the resource component for which the WS-Resource
provides access. This resource component can either be an existing
system or entity, or a new component. You have no constraints on how you implement
the resource; it can be a simple Java class, a stateless session enterprise
bean, an entity bean backed by a relational database, a Service Data Object
(SDO), a Java connector, or any other component.
- Identify or create a resource properties schema document for the
WS-Resource. Use the WebSphere Application Server Toolkit, or any
XML schema authoring tool, to create an XML schema. The schema defines the
XML complexType element for the root element of the resource properties document.
- Create or generate a WSDL document for the Web service component
of the WS-Resource. See Developing a WSDL file for JAX-RPC applications for
information about creating WSDL files.
- Edit the WSDL file to add a ResourceProperties attribute to the
portType element. This attribute identifies the root element of the resource
properties document that you created earlier. For example, if
a Printer service has a resource properties document with a root element <printer_properties>
in the namespace http://example.org/printer, then the wsdl:portType element
might look as follows:
<wsdl:portType xmlns:pr="http://example.org/printer"
xmlns:wsrf-rp="http://docs.oasis-open.org/wsrf/rp-2"
name="Printer" wsrf-rp:ResourceProperties="pr:printer_properties">
- Provide a means to obtain an EndpointReference that points to the
WS-Resource. You might define a wsdl:operation element called
Create that returns a wsdl:output message of type EndpointReferenceType. See Example: Creating a Web service that uses the Web Services Addressing
API to access a Web Services Resource (WS-Resource) instance for an example of a CreatePrinter
operation that returns an EndpointReference object for a Printer WS-Resource.
- Define each WSRF-defined operation that the WS-Resource supports
as a child element of the wsdl:portType element. For each WSRF-defined
operation that is supported by the port type, specify the WS-Addressing action attribute on each wsdl:message element.
For example, the GetResourceProperty operation is defined in the
WSDL as follows:
<wsdl:operation name="GetResourceProperty"
xmlns:wsaw="http://www.w3.org/2006/05/addressing/wsdl"
xmlns:wsrf-rpw="http://docs.oasis-open.org/wsrf/rpw-2">
<wsdl:input name="GetResourcePropertyRequest" message="wsrf-rpw:GetResourcePropertyRequest"
wsaw:Action="http://docs.oasis-open.org/wsrf/rpw-2/GetResourceProperty/GetResourcePropertyRequest"/>
<wsdl:output name="GetResourcePropertyResponse" message="wsrf-rpw:GetResourcePropertyResponse"
wsaw:Action="http://docs.oasis-open.org/wsrf/rpw-2/GetResourceProperty/GetResourcePropertyResponse"/>
...
</wsdl:operation>
The wsaw:Action attribute ensures that the WSRF-defined wsaw:Action
URIs are used for the WSRF-defined messages, rather than default URI values.
Note: The
WS-ResourceProperties specification requires the presence of the GetResourceProperty
operation if the ResourceProperties attribute is present on the PortType element.
- Follow the instructions from step 2 in Creating a Web service application that is referenced through a Web
Services Addressing endpoint reference to create the implementation of
the WS-Resource, enable the client to access the WS-Resource using an endpoint
reference, and deploy the application.
What to do next
Review Example: Creating a Web service that uses the Web Services Addressing
API to access a Web Services Resource (WS-Resource) instance for
sample WS-Resource code.
}
Web Services Resource Framework support
Web Services Resource Framework resource property and lifecycle operations
Example: Creating a Web service that uses the Web Services Addressing
API to access a Web Services Resource (WS-Resource) instance
Related concepts
Web Services Addressing support
Related tasks
Creating a Web service application that is referenced through a Web
Services Addressing endpoint reference
Task overview: Implementing Web services applications
Related Reference
WSDL2Java command for JAX-RPC applications
Java2WSDL command for JAX-RPC applications
Related information
Web Services Addressing application programming model OASIS WSRF primer
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