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java.lang.NoClassDefFoundError: Could not initialize class com.amazonaws.ClientConfiguration

Using this bundle - aws-java-sdk-osgi-1.11.26.jar in OSGI Server
Below Error is thrown when this is executed AmazonS3 s3 = new AmazonS3Client( credentials );
java.lang.NoClassDefFoundError: Could not initialize class com.amazonaws.ClientConfiguration
at com.amazonaws.ClientConfigurationFactory.getDefaultConfig(ClientConfigurationFactory.java:46)
at com.amazonaws.ClientConfigurationFactory.getConfig(ClientConfigurationFactory.java:36)
at com.amazonaws.services.s3.AmazonS3Client.<init>(AmazonS3Client.java:440)
Any solution to fix this?

Thanks for all suggestions
The ClientConfiguration of
aws-java-sdk-osgi-1.11.26.jar is dependent of Jackson-databind.jar
Jackson-databind.jar is dependent on Jackson-core.jar
So it is not able to initialize ClientConfiguration.
Added Import-Package importing all from jackson-core-osgi.jar in Manifest of Jackson-databind-osgi.jar
Then the issue is resolved
Note: All dependent jars are converted to OSGI jars and deployed

Well, make sure that aws-java-sdk-osgi-1.11.26.jar is present on your classpath, because the class itself is present in the jar.
I've just downloaded the jar.

I guess you are missing an Import-Package statement in your bundle Manifest. Not sure how you build your bundle but I would recommend to use bnd in some form for it. For example I typically use the maven-bundle-plugin which uses bnd under the hood. Bnd is able to figure out the imports automatically for most cases.

In my case, restarting the flink cluster solved the problem.

how to fix missing requirement while the deployment of an OSGI bundle

I am trying to deploy a simple OSGI bundle (hello world) in glassfish 4.1.1 but I got the following error:
Infos: org.osgi.framework.BundleException:
Unresolved constraint in bundle com.mycompany.MavenHelloServiceImpl [324]:
Unable to resolve 324.0: missing requirement [324.0]
osgi.wiring.package; (osgi.wiring.package=com.mycompany.mavenhelloserviceapi)
at org.apache.felix.framework.Felix.resolveBundleRevision(Felix.java:3974)
I don't know how to fix the missing package , I already defined "com.mycompany.mavenhelloserviceapi" as a dependency in the bundle MavenHelloServiceImpl and it is present in the dependencies folder in the bundle MavenHelloServiceImpl
Any idea how to fix this error ?!

Having com.mycompany.mavenhelloserviceapi as a dependency in your pom.xml is not enough : the pom is about compile-time dependencies. you see here an issue about a runtime dependency missing.
You should install com.mycompany.mavenhelloserviceapi in your container.

You should modify the project that contains com.mycompany.mavenhelloserviceapi as a bundle project and explicitly export this package. now deploy this bundle alongwith your hello world bundle.
Alternatively ,you can use Pax Wrap to deploy the jar that contains com.mycompany.mavenhelloserviceapi to glassfish without modifying the project.

Can't get a working reference to an OSGi service

I'm trying to embed apache felix into a simple hello world java project with maven, but I can't find a way to get a reference to a service of a bundle. I've installed org.apache.felix.bundlerepository bundle into OSGi from a jar and also added it as a maven dependency to my project. After that I'm starting the bundle, getting BundleContext from it and then calling getServiceReference(RepositoryAdmin.class.getName()) on that bundle context. The first thing I'm unhappy with is that I have to use BundleContext from the installed bundle, if I'd use BundleContext of the Framework the ServiceReference will be always null. This is not convinient.
The second, more important issue, is that when I finally receiving a reference to RepositoryAdmin service from bundlerepository bundle I can't cast it to org.apache.felix.bundlerepository.RepositoryAdmin, executing the following code:
(RepositoryAdmin)admin.getBundleContext().getService(ref)
will throw this exception:
java.lang.ClassCastException: org.apache.felix.bundlerepository.impl.RepositoryAdminImpl cannot be cast to org.apache.felix.bundlerepository.RepositoryAdmin
I know this is a kind of classpath issue and may be caused by incompatibility of interfaces, but I'm using a bundle jar of the same version (2.0.2) as a maven dependency of my project.
I'm also aware of Constants.FRAMEWORK_SYSTEMPACKAGES_EXTRA osgi configuration option which should force a bundle to use a package from the host application, but it didnt help me.
Here is the main class of my project https://github.com/ArtemZ/osgi-study/blob/master/src/main/java/com/artemz/demo/Main.java which is messy because I was trying different things on it in order to get a reference to a service, but none actually worked for me.
Hope someone will help me, because I'm really desperate with this issue.

Thanks for giving some more details about what you are doing. I already followed the mails on the felix list.
Now I think I understand what happens. The reason why you can not get the service from outside the RepositoryAdmin bundle is that the package you define in
FRAMEWORK_SYSTEMPACKAGES_EXTRA is "org.apache.felix.bundlerepository; version=2.0.2"
is not the same version as the package from the RepositoryAdmin bundle. I downloaded the bundle and looked into the Manifest:
Export-Package: org.osgi.service.repository;version="1.0";uses:="org.osg
i.resource",org.apache.felix.bundlerepository;version="2.1";uses:="org.
osgi.framework"
So as you see the version you should export from the system bundle is 2.1 not 2.0.2.
In OSGi the versions are defined per package not on the bundle level. So while most times they are the same this is not always true. Espcecially for OSGi spec packages.
So when the package version are different you have two effects:
1. You will not be able to find a service with a different package
2. If you get a service object in some other way like you did then you will have a class cast exception as they are loaded by different classloaders.
So can you try the 2.1 version and report if it works?

REST client inside of OSGi application

I need to integrate a REST client into an existing OSGi application implemented using Apache Felix. The REST service is based on RESTeasy implementation (version 2.3.2.Final) of JAX-RS. I created a separate bundle with clients' dependencies, exporting required RESTeasy packages and importing them in the bundle where the client is used, but unfortunately I cannot get it working inside of the OSGi context.
I tried two different approaches. First one using the generic ClientRequest:
ClientRequest request = new ClientRequest(MyService.URL_TEST+"/stats");
request.body(javax.ws.rs.core.MediaType.APPLICATION_XML, stats);
ClientResponse<String> response = request.post(String.class);
The error that I get in this case is pretty weird:
[java] java.lang.RuntimeException: java.lang.ClassCastException:
org.jboss.resteasy.client.core.executors.ApacheHttpClient4Executor cannot be cast to
org.jboss.resteasy.client.ClientExecutor
where I it is known for sure that ApacheHttpClient4Executor implements the ClientExecutor interface.
When I try to use my own REST client wrapper around RESTeasy like this:
MyService myService = MyServiceClient.getInstance();
myService.saveStatistics(stats);
I get a different exception:
[java] java.lang.LinkageError: ClassCastException: attempting to
castjar:file:/D:/Development/Eclipses/eclipse_4.2_j2ee_x64/lib/jaxrs-api-2.3.2.Final.jar
!/javax/ws/rs/ext/RuntimeDelegate.classtobundle:
//78.0:1/javax/ws/rs/ext/RuntimeDelegate.class
As far as I understand, the LinkageError most probably has to do with the way RESTeasy initializes the RuntimeDelegate using some classloader tricks, which probably fall under the restrictions of OSGi framework. I get the suspicion that the java.lang.ClassCastException mentioned first has the same source.
Is there any way to get RESTeasy working inside of OSGi?
PS: discussion about a similar issue with RESTeasy, but outside of OSGi: java.lang.LinkageError: ClassCastException
Update:
these are the libraries included into restclient bundle:
activation-1.1.jar commons-codec-1.2.jar commons-httpclient-3.1.jar commons-io-2.1.jar commons-logging-1.0.4.jar flexjson-2.1.jar httpclient-4.1.2.jar httpcore-4.1.2.jar javassist-3.12.1.GA.jar jaxb-api-2.2.3.jar jaxb-impl-2.2.4.jar jaxrs-api-2.3.2.Final.jar jcip-annotations-1.0.jar jettison-1.3.1.jar jsr250-api-1.0.jar junit-4.10.jar log4j-1.2.14.jar resteasy-jaxb-provider-2.3.2.Final.jar resteasy-jaxrs-2.3.2.Final.jar resteasy-jettison-provider-2.3.2.Final.jar scannotation-1.0.3.jar slf4j-api-1.6.4.jar slf4j-log4j12-1.6.4.jar myservice-common-0.1.0.3.jar my-service-client-0.1.0.3-SNAPSHOT.jar stax-api-1.0-2.jar xmlpull-1.1.3.1.jar xpp3_min-1.1.4c.jar xstream-1.4.2.jar
These are the exports from the restclient bundle: javax.ws.rs, javax.ws.rs.ext, javax.ws.rs.core, org.jboss.resteasy.client, org.jboss.resteasy.client.cache, org.jboss.resteasy.client.extractors, org.jboss.resteasy.client.marshallers, org.jboss.resteasy.client.core.executors, javax.xml.bind.annotation, org.jboss.resteasy.plugins.providers, org.jboss.resteasy.plugins.providers.jaxb, org.jboss.resteasy.spi

Have a look at the SpringSource Bundle Repo, it's got some very useful pre-built bundles of common libraries including the Apache HTTP Client which we are using (in conjunction with gson) to do our RESTful comms.

(unfortunately a legacy module of my project still uses OSGi, but using RESTeasy 3.0.16 now)
When I need to OSGify a dependency my preferred solution now is to wrap it using the excellent Apache Ops4j Pax Tipi project.
The project provides a preconfigured Maven setup (parent POM handles the bundling) and you just have to adapt the GAV coordinates of the original project in a Tipi sub module with a org.apache.ops4j.pax.tipi prefix and build the new bundle project which draws in the original dependency, unpacks and wraps it as OSGi bundle.
You can start from an existing Tipi sub project that best matches your project setup (dependencies, etc.) and adapt any OSGi imports/exports missing (most often, these are created automatically by the maven-bundle-plugin anyway).
This worked quite well for me as long as the original project did not contain too many exotic or malformed dependencies.
However you may run into snags like transitive dependencies using the root package, as I currently experience, which can be a real show stopper (finding out which library is a real nightmare).
Unfortunately, RESTeasy seems to be affected by this, as I get exactly the same error (default package , even after declaring non-test and non-provided dependencies as optional:
The default package '.' is not permitted by the Import-Package syntax.
Upgrading the maven-bundle-plugin to the latest release 3.0.1 yields a different error (even less helpful):
[ERROR] Bundle org.ops4j.pax.tipi:org.ops4j.pax.tipi.resteasy-jaxrs:bundle:3.0.16.Final.1 : Can not parse name from bundle native code header:
[ERROR] Error(s) found in bundle configuration
Update seems to be solved by upping Tipi version in POM to 1.4.0, testing...

Is RESTEasy mandatory ?
I personally use jersey in OSGi and it is working perfectly, both as client and server.

This problem isn't limited to RESTeasy. It also occurs with Jersey.
It is occurring because you have two copies of the JAX-RS classes on the classpath.
You can see this in the LinkageError:
[java] java.lang.LinkageError: ClassCastException: attempting to cast jar:file:/D:/Development/Eclipses/eclipse_4.2_j2ee_x64/lib/jaxrs-api-2.3.2.Final.jar!/javax/ws/rs/ext/RuntimeDelegate.class to bundle://78.0:1/javax/ws/rs/ext/RuntimeDelegate.class
i.e. one copy is coming from:
D:/Development/Eclipses/eclipse_4.2_j2ee_x64/lib/jaxrs-api-2.3.2.Final.jar
and the other from the OSGI bundle.
This causes problems for the RuntimeDelegate class, which by default uses the system class loader to create the RuntimeDelegate implementation (see javax.ws.rs.ext.FactoryFinder).
The problem can also occur if the same jar is loaded via two different class loaders.
There are a couple of workarounds:
remove the jaxrs-api-2.3.2.Final.jar from the system class path
set the thread context class loader to that of your bundle, prior to making any JAX-RS calls.
The FactoryFinder will use this to load the RuntimeDelegate.
To avoid polluting your code with calls to Thread.currentThread().setContextClassLoader(myBundleClassLoader), you can wrap your JAX-RS client using a Proxy. e.g. see the Thread context classloader section of https://puredanger.github.io/tech.puredanger.com/2007/06/15/classloaders/

Package uses conflict: Import-Package: de.foo.bar; version="0.0.0"

I try to install a bundle in an OSGi environment (FUSE ESB) but do not manage to get it resolved. The error message is:
The bundle could not be resolved. Reason: Package uses conflict: Import-Package: de.foo.bar; version="0.0.0"
My bundle imports the package de.foo.bar.
The bundle which exports the package de.foo.bar does this with a 'uses' directive.
Export-Package = de.foo.bar;uses:="{other packages}";version="2.4.0"
As I understood I have to ensure that my bundle must import all other packages mentioned in the 'uses' directive of the de.foo.bar package (in the right version).
I checked this and also tried several version changes (0.0.0 and the real version numbers) but can not get it to work.
So, what does the error message realy means (maybe I understood it wrong)? What do I have to check?
Thanks for any help
Klaus
System Information:
FUSE ESB 4.2.0 (based on servicemix)
using maven-bundle-plugin 2.1.0 to generate OSGi MANIFEST header

I finally found what was wrong.
My bundle is a Spring Dynamic Module bundle and I did a mistake in the spring bean configuration (use a 'ref' instead a 'value' in a constructor-arg). Normally spring configuration errors are reported as such - I do not know why the current error resulted in the misleading message.
EDIT:
The faulty Spring configuration does not cause the uses conflict. It finally was the import of the package org.apache.log4j which is exported by different bundles (in my FUSE ESB container) and apparently was different wired to the bundles I tried to install.
Trying to solve my problem I found the article Diagnosing OSGi uses conflicts which I found helpfull to understand the problem.