Hi everyone,
For those interested, I found the solution to my problem:
By looking in Felix SCR source code I found the lines causing the
exception:
// field value type
if ( !m_isMultiple )
{
// value type must not be specified for unary references
if ( m_field_collection_type != null )
{
throw componentMetadata.validationFailure( "Field value type
must not be set for unary field references." );
}
}
It seems Felix SCR is not happy because the attribute
m_field_collection_type is set to "service" in the component XML (i.e.
not null), while no cardinality is specified...
I thus changed my annotation like this:
@Reference(cardinality = ReferenceCardinality.AT_LEAST_ONE)
private List<FileReaderService> availableServices;
I also added a factory service consumer in order to test the application
and it works!
For those interested, the fixed source code is available here:
https://github.com/neopium/FileReader
Kind regards,
Ben
Le 12.01.2016 11:21, [email protected] a écrit :
Hi David,
I just pushed my sample project on GitHub:
https://github.com/neopium/FileReader
You can get it from here and build it. I configured it so that it
generates a Karaf assembly with the required feature. When you start
karaf and type scr:list, you see the two readers with null status. The
factory is not there.
Here is the generated component xml file:
<?xml version="1.0" encoding="UTF-8"?>
<scr:component xmlns:scr="http://www.osgi.org/xmlns/scr/v1.3.0";
name="org.test.reader.service.factory.FileReaderFactory">
<implementation
class="org.test.reader.service.factory.FileReaderFactory"/>
<service>
<provide interface="org.test.reader.service.ReaderFactoryService"/>
</service>
<reference name="availableServices"
interface="org.test.reader.service.FileReaderService"
field="availableServices" field-collection-type="service"/>
</scr:component>
Here is the full stacktrace:
2016-01-12 11:12:36,961 | ERROR | pool-8-thread-1 |
file-reader-service-impl | 9 - file-reader-service-impl -
1.0.0.SNAPSHOT | [org.test.reader.service.factory.FileReaderFactory]
Cannot register Component
org.osgi.service.component.ComponentException: Component
org.test.reader.service.factory.FileReaderFactory validation failed:
Field value type must not be set for unary field references.
at
org.apache.felix.scr.impl.metadata.ComponentMetadata.validationFailure(ComponentMetadata.java:953)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.metadata.ReferenceMetadata.validate(ReferenceMetadata.java:710)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.metadata.ComponentMetadata.validate(ComponentMetadata.java:873)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.BundleComponentActivator.loadDescriptor(BundleComponentActivator.java:454)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.BundleComponentActivator.initialize(BundleComponentActivator.java:309)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.BundleComponentActivator.<init>(BundleComponentActivator.java:270)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.Activator.loadComponents(Activator.java:358)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.Activator.access$000(Activator.java:53)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.scr.impl.Activator$ScrExtension.start(Activator.java:260)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.utils.extender.AbstractExtender.createExtension(AbstractExtender.java:259)[24:org.apache.felix.scr:2.0.2]
at
org.apache.felix.utils.extender.AbstractExtender.modifiedBundle(AbstractExtender.java:232)[24:org.apache.felix.scr:2.0.2]
at
org.osgi.util.tracker.BundleTracker$Tracked.customizerModified(BundleTracker.java:482)[org.osgi.core-6.0.0.jar:]
at
org.osgi.util.tracker.BundleTracker$Tracked.customizerModified(BundleTracker.java:415)[org.osgi.core-6.0.0.jar:]
at
org.osgi.util.tracker.AbstractTracked.track(AbstractTracked.java:232)[org.osgi.core-6.0.0.jar:]
at
org.osgi.util.tracker.BundleTracker$Tracked.bundleChanged(BundleTracker.java:444)[org.osgi.core-6.0.0.jar:]
at
org.apache.felix.framework.util.EventDispatcher.invokeBundleListenerCallback(EventDispatcher.java:916)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.util.EventDispatcher.fireEventImmediately(EventDispatcher.java:835)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.util.EventDispatcher.fireBundleEvent(EventDispatcher.java:517)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.Felix.fireBundleEvent(Felix.java:4541)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.Felix.startBundle(Felix.java:2172)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.BundleImpl.start(BundleImpl.java:998)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.felix.framework.BundleImpl.start(BundleImpl.java:984)[org.apache.felix.framework-5.4.0.jar:]
at
org.apache.karaf.features.internal.service.FeaturesServiceImpl.startBundle(FeaturesServiceImpl.java:1189)[7:org.apache.karaf.features.core:4.0.3]
at
org.apache.karaf.features.internal.service.Deployer.deploy(Deployer.java:836)[7:org.apache.karaf.features.core:4.0.3]
at
org.apache.karaf.features.internal.service.FeaturesServiceImpl.doProvision(FeaturesServiceImpl.java:1079)[7:org.apache.karaf.features.core:4.0.3]
at
org.apache.karaf.features.internal.service.FeaturesServiceImpl$1.call(FeaturesServiceImpl.java:975)[7:org.apache.karaf.features.core:4.0.3]
at
java.util.concurrent.FutureTask.run(FutureTask.java:266)[:1.8.0_65]
at
java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)[:1.8.0_65]
at
java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)[:1.8.0_65]
at java.lang.Thread.run(Thread.java:745)[:1.8.0_65]
Le 11.01.2016 19:54, David Jencks a écrit :
Well, you got farther anyway :-) I don’t yet see what’s wrong. Could
you supply the generated component xml and the ComponentException
stack trace?
With bnd 3+ you don’t (shouldn’t?) need to specify
(service=FileReader.class) as now bnd can analyze the generic
method/field signature to infer the service type.
thanks
david jencks
On Jan 11, 2016, at 9:56 AM, [email protected] wrote:
Thanks David,
I tried that by get an error on karaf startup:
cannot register Component
org.osgi.service.component.ComponentException: Component
FileReaderFactory validation failed: Field value type must not be set
for unary field references.
My class looks like this:
@Component
public class FileReaderFactory implements ReaderManager {
@Reference(service = FileReader.class)
private List<FileReader> availableServices;
@Override
public Data readFile(Path filePath) throws IOException {
for (FileReader reader : availableServices) {
if (reader.isFormatSupported(filePath)) {
return reader.readFile(filePath);
}
}
return null;
}
@Override
public boolean isFormatSupported(Path filePath) throws IOException
{
for (FileReader reader : availableServices) {
if (reader.isFormatSupported(filePath)) {
return true;
}
}
return false;
}
}
Le 11.01.2016 18:47, David Jencks a écrit :
Well, you need cmpn 6 for the ds 1.3 annotations (in particular
@Reference applicable to a field). I thought this was on maven
central but haven’t looked. If necessary you can get it from the
OSGI
site.
david jencks
On Jan 11, 2016, at 12:35 AM, [email protected] wrote:
Hi everyone!
I asked a question on stackoverflow regarding the use of
Declarative Services in Karaf to manage multiple instances of a
service, provided by different implementations of such a service.
The question is explained in details here:
http://stackoverflow.com/questions/34706041/how-to-manage-several-service-instances-in-declarative-services
I received and answer telling me that using the @reference
annotation on the list storing the services would solve my problem.
For this, I would need to use DS 1.3.
I thus asked on Karaf users mailing list what was the version of
Felix SCR provided with Karaf 4.0.3
(http://mail-archives.apache.org/mod_mbox/karaf-user/201601.mbox/%3C8dbfa59508d5769609e2c78c0210c7aa%40petinou.fr%3E)
and was told it was Felix SCR 2.0.2, which supports DS 1.3. So far
so good.
I was also kindly advised to ask this kind of questions here. So
here I am :-)
Following the answer on stackoverflow, I tried to add the
@reference annotation to my service list like this:
@Reference(service = FileReader.class)
private List<FileReader> availableServices = new ArrayList<>();
But it does not compile: FileReaderFactory.java:[37,5] annotation
type not applicable to this kind of declaration
My project has a dependency on:
<dependency>
<groupId>org.osgi</groupId>
<artifactId>org.osgi.compendium</artifactId>
<version>5.0.0</version>
<scope>provided</scope>
</dependency>
which seems to be the latest version available.
I thus tried the "older way" by using explicit bind/unbind methods
like this:
@Reference(service = FileReader.class, unbind = "removeService")
public void addService(final FileReader serviceToAdd) {
System.out.println("FileReaderFactory.addService");
availableServices.add(serviceToAdd);
System.out.println(availableServices);
}
public void removeService(final FileReader serviceToRemove) {
System.out.println("FileReaderFactory.removeService");
availableServices.remove(serviceToRemove);
System.out.println(availableServices);
}
If I have two implementations available, say TxtFileReader and
XmlFileReader, only the first one is added to the list. The status
of the second service (using scr:detail command) is "null".
What am I missing?
Kind regards,
Ben
