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• The Greeter Interface bundle
• The Greeter Service Implementation bundle
• The Greeter Service Consumer bundle

The Greeter Interface bundle exports the GreeterService interface which both other bundles depend on. This is the interface:

public interface GreeterService {
    Map<GreetingPhrase, String> greetMe(String name);
    GreetingPhrase [] greetMe(GreeterData name) throws GreeterException;
}

The GreeterData interface, GreetingPhase and GreeterException classes are

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custom types defined in the Greeter Interface bundle.

In this walkthrough, the following setup will be used:

The client side bundles will be running in Equinox, invoking on a Distributed OSGi Service running in Felix. Note that the choice of containers is completely trivial. Any OSGi container that implements the Service Registry Hooks (a new feature in OSGi 4.2) can be used on either side.

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Let's run the server in Felix 13.80.01. As a prerequisite it requires some of the OSGi Compendium Specification interfaces. These don't come with the Felix download, but you can install a bundle that contains these interfaces straight from the Felix download areaMaven.
In this walkthrough I'm using the single-bundle distribution of CXF/DOSGi which can be installed straight from the Maven release repository.

To set up my Felix environment, I'm running the following commands:

C:\felix-framework-13.8.0>java -jar bin\felix.jar0.1>

Welcome to Apache Felix.
=================

-> ps
START LEVEL 1
   ID   State     Gogo
g! install http://repo1.maven.org/maven2/org/osgi/org.osgi.compendium/4.2.0/org.osgi.compendium-4.2.0.jar
g! start http://www.apache.org/dist/cxf/dosgi/1.2/cxf-dosgi-ri-singlebundle-distribution-1.2.jar
... some log messages may appear...
g! lb
    0|Active     Level|  Name
[  0|org.apache.felix.framework 0] [Active(3.0.1)
    1|Active  ] [  |  0] System Bundle 1|org.apache.felix.bundlerepository (1.86.02)
[   1] [2|Active     ] [|    1] Apache Felix Shell Service (1.2|org.apache.felix.gogo.command (0.6.0)
[   2] [3|Active     ] [|    1] Apache Felix Shell TUI (1.2|org.apache.felix.gogo.runtime (0.6.0)
[   3] [4|Active     ]| [    1] Apache Felix Bundle Repository (1.4.0)
-> start http://www.apache.org/dist/felix/org.osgi.compendium-11|org.apache.felix.gogo.shell (0.6.0)
    5|Resolved   |    1|osgi.cmpn (4.2.0.jar
-> start https://repository.apache.org/content/groups/snapshots/org/apache/cxf/dosgi/cxf-dosgi-ri-singlebundle-distribution/1.1-SNAPSHOT/200908310645)
    6|Active     |    1|cxf-dosgi-ri-singlebundle-distribution- (1.1-SNAPSHOT.jar
2.0)

Some log messages may come up now.
Note that instead of manually adding these bundles to the Felix container, you can also append the target/felix.config.properties.append file to the <felix-root>/conf/config.properties file. This will automatically load these two bundles when Felix starts up.

Now let's start up the server-side greeter bundles. Like with the DOSGi bundle itself, I'm installing these straight from the Maven release repository.

->g! start http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-interface/1.02/cxf-dosgi-ri-samples-greeter-interface-1.02.jar
->g! start http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-impl/1.02/cxf-dosgi-ri-samples-greeter-impl-1.02.jar
-> ps... some log messages will appear ...
g! lb
START LEVEL 1
   ID   |State         Level  |Level|Name
[    0] [|Active     ] [|    0] |System Bundle (13.80.01)
[    1] [|Active     ]| [    1] |Apache Felix ShellBundle ServiceRepository (1.6.2.0)
[    2] [|Active     ] [|    1] |Apache Felix ShellGogo TUICommand (10.26.0)
[    3] [|Active     ] [|    1] |Apache Felix BundleGogo RepositoryRuntime (10.46.0)
[    4] [Active     ] [    1] OSGi R4 Compendium Bundle|Active     |    1|Apache Felix Gogo Shell (0.6.0)
    5|Resolved   |    1|osgi.cmpn (4.12.0.200908310645)
[   5] [6|Active     ] [|    1] |Distributed OSGi Distribution Software Single-Bundle Distribution
[   8] [7|Active     ]| [    1] |CXF Distributed OSGi Greeter Demo Interface Bundle
[   9] [8|Active     ] [|    1] |CXF Distributed OSGi Greeter Demo Service Implementation Bundle

At the end of the log messages you will see one appear that says:
INFO: TopologyManager: export sucessful Endpoints: Endpoint Description for ServiceReference [Some more log messages come up. When it says INFO: Remote org.apache.cxf.dosgi.samples.greeter.GreeterService endpoint has been published into Discovery service you know ]
This means that the service is successfully exposed remotely, and you can verify this by requesting the WSDL:

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So the remote service is simply looked up the normal way, via the OSGi Service Registry.
How does it get there? The fact that a lookup on a service is done internally triggers a Service Registry Hook. This will go out to any registered Distributed OSGi Discovery implementations and query them for any matching services.
However, in our setup we haven't yet registered a Discovery implementation. There is an alternative, more static way to provide discovery type information, in case this info is not available via discovery. It can be specified in a OSGI-INF/remote-service/*.xml file. This the content of the Greeter Service Consumer remote-services.xml file:

<endpoint<service-descriptions xmlns="http://www.osgi.org/xmlns/sdrsa/v1.0.0">
  <service<endpoint-description>
    <provide<property interfacename="org"objectClass">
      <array>
        <value>org.apache.cxf.dosgi.samples.greeter.GreeterService"GreeterService</>value>
      </array>
  <property name="service.exported.interfaces">*  </property>
    <property name="serviceendpoint.exported.configs">org.apache.cxf.ws<id">http://localhost:9090/greeter</property>
    <property name="orgservice.imported.configs">org.apache.cxf.ws.address">http://localhost:9090/greeter<ws</property>
  </serviceendpoint-description>
</serviceendpoint-descriptions>

Let's run the consumer in Equinox, so that we have the bundles running in Equinox talking to a remoted service running in Felix!
As with Felix, we will have to load the bundle with the OSGi compendium interfaces. There's one that ships with Equinox.

/eclipse> java -jar plugins/org.eclipse.osgi_3.56.0.v20081201-1815v20100517.jar -configuration conf -console
osgi> install install file:plugins/org.eclipse.osgi.services_3.2.0100.v20081205-1800v20100503.jar
Bundle id is 1
osgi> start 1

osgi> install httpshttp://repositorywww.apache.org/content/groups/snapshots/org/apache/dist/cxf/dosgi/cxf-dosgi-ri-singlebundle-distribution/1.1-SNAPSHOT2/cxf-dosgi-ri-singlebundle-distribution-1.1-SNAPSHOT2.jar
Bundle id is 2

osgi> start 2
... some log messages may appear...

Some logging messages may appear. You can also automatically load the DOSGi bundles by appending the target/equinox.config.ini.append to you equinox config.ini file.

osgi> install http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-interface/1.02/cxf-dosgi-ri-samples-greeter-interface-1.02.jar
Bundle id is 3
osgi> install http://repo2repo1.maven.org/maven2/org/apache/cxf/dosgi/samples/cxf-dosgi-ri-samples-greeter-client/1.02/cxf-dosgi-ri-samples-greeter-client-1.02.jar
Bundle id is 4
osgi> ss

Framework is launched.

id      State       Bundle
0       ACTIVE      org.eclipse.osgi_3.56.0.v20081201-1815v20100517
1       ACTIVE  RESOLVED    org.eclipse.osgi.services_3.2.0100.v20081205-1800v20100503
2       ACTIVE      cxf-dosgi-ri-singlebundle-distribution
3       INSTALLED   cxf-dosgi-ri-samples-greeter-interface
4       INSTALLED   cxf-dosgi-ri-samples-greeter-client

osgi> start 4

After a few moments the following window appears:

Image RemovedImage Added

The window appears once the ServiceTracker in the consumer has received a callback that the GreeterService has been found. The value entered will used to invoke the (remote) OSGi service, with a call like this:

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