Table of Contents
This chapter aims at illustrate building of distributed applications with SCA. In the first section we will use the previous HelloWorld example. We will show that client and server components can be distributed easily using the composite definition. In the second section we will give an example of an SCA client which use webservice binding to call a weather service over Internet.
This section will show how to expose an SCA service as a web service, or how to bind an SCA reference to external web service.
Exporting an SCA service as a web service is very easy, as it
doesn't require any SCA specific code. It is sufficient to add a
binding.ws element as subelement of the service
definition and to define the URI to which make available the web
service.
No SCA specific code is needed.
1 <?xml version="1.0" encoding="ISO-8859-15"?>
2 <composite xmlns="http://www.osoa.org/xmlns/sca/1.0"
3 name="helloworld-ws-server">
4
5 <component name="server">
6 <implementation.java class="org.ow2.frascati.examples.helloworld.annotated.Server"/>
7 <service name="printService">
8 <binding.ws uri="http://localhost:8080/PrintService"/>
9 </service>
10 </component>
11
12 </composite>
13
The PrintService is now available as a web service.
Using this service is easily doable by setting the webservice binding
on the client component.
1 <?xml version="1.0" encoding="ISO-8859-15"?> 2 <composite xmlns="http://www.osoa.org/xmlns/sca/1.0" 3 xmlns:wsdli="http://www.w3.org/2004/08/wsdl-instance" 4 name="helloworld-ws-client"> 5 6 <service name="r" promote="client/r"> 7 <interface.java interface="java.lang.Runnable" /> 8 </service> 9 10 <component name="client"> 11 <reference name="printService"> 12 <binding.ws wsdli:wsdlLocation="http://localhost:8080/PrintService?wsdl" 13 wsdlElement="http://annotated.helloworld.examples.frascati.ow2.org#wsdl.port(PrintService/PrintServicePort)"/> 14 </reference> 15 <implementation.java class="org.ow2.frascati.examples.helloworld.annotated.Client" /> 16 </component> 17 18 </composite> 19
localhost with the
IP or name of the host.