How to properly include Spring into an OSGified bundle

Question

I have a very simple OSGI app that just listens on register/unregister and sends some message to stdout.

What I have in my app is a simple Spring initialized bean. I use the maven bundle plugin to bundle the jar and put it into felix. This is an exceprt of the pom:

<dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>3.1.0.RELEASE</version>
        <type>jar</type>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.felix</groupId>
            <artifactId>maven-bundle-plugin</artifactId>
            <version>2.2.0</version>
            <extensions>true</extensions>
            <configuration>
                <instructions>
                    <Export-Package>org.spring.*</Export-Package>
                    <Bundle-Activator>foo.bar.Activator</Bundle-Activator>
                </instructions>
            </configuration>
        </plugin>
    </plugins>
</build>

The project compiles just fine and can be deployed into Felix just fine, however, when the activator is called, it complains about missing dependency like that:

Unresolved constraint in bundle foo.bar.project [56]: Unable to resolve 56.0: missing requirement [56.0] osgi.wiring.package; (&(osgi.wiring.package=org.springframework.context)(version>=3.1.0)(!(version>=4.0.0)))

I tried changing this line:

org.spring.*

To this:

*

In which felix complains that android-dalvik is not present, so I am completely clueless.

Any idea how to include Spring in an OSGI project without using Spring DM?

EDIT: Here is what the generated manifest complains about (from web console)

Exported Packages

foo.bar.osgi foo.bar.service foobar.tracker

Imported Packages org.osgi.framework,version=[1.6,2) from org.apache.felix.framework (0) org.osgi.util.tracker,version=[1.5,2) from org.apache.felix.framework (0) ERROR: org.springframework.context,version=[3.1,4) -- Cannot be resolved ERROR: org.springframework.context.support,version=[3.1,4) -- Cannot be resolved

Manifest Headers Bnd-LastModified: 1339014840268

Build-Jdk: 1.6.0_32

Built-By: fooBar

Bundle-Activator: foo.bar.osgi.Activator

Bundle-ManifestVersion: 2

Bundle-Name: fooBar

Bundle-SymbolicName: foo.bar.OSGIProject

Bundle-Version: 0.20.0.SNAPSHOT

Created-By: Apache Maven Bundle Plugin

Export-Package: foo.bar.osgi.tracker; uses:="foo.bar.osgi.service, org.osgi.util.tracker, org.osgi.framework",

foo.bar.osgi; uses:="org.springframework.context.support, org.springframework.context, org.osgi.framework", foo.bar.osgi.service

Import-Package:

org.osgi.framework; version="[1.6, 2)", org.osgi.util.tracker; version="[1.5, 2)", org.springframework.context; version="[3.1, 4)", org.springframework.context.support; version="[3.1, 4)" Manifest-Version: 1.0 Tool: Bnd-1.15.0

This is when I changed in pom

<configuration>
    <instructions>
        <Include-Resource>src/main/resources/spring-beans.xml</Include-Resource>
        <Bundle-Activator>nl.synovite.scheduled.osgi.Activator</Bundle-Activator>
        <Import-Package>*</Import-Package>></instructions>
</configuration>

Can you post the generated MANIFEST.MF? And why are you exporting "org.spring"? Is that the package name of your code base? — Jonathan W
I think org.spring.* is being exported as a way of re-packaging every spring dependency into the built bundle. If you must repackage spring in your bundle (which isn't really in the modularity spirit of OSGi, imo), <Private-Package> might be better than <Export-Package>. This at least avoids exposing all the spring internals. — Holly Cummins
Private package is indeed a better choice in this case (actually as far as I know, privatePackage is discarded in manifest by most OSGI providers). However, private or no, spring is not packaged at all into the jar. So I went ahead and added all spring dependencies in felix as osgified artifacts. — Nikola Yovchev
Private-package is, as you say, a build instruction rather than a runtime one. This avoids mixing build concerns with runtime behaviour. (See my answer below for why neither instruction packages spring.) — Holly Cummins

Frank Lee Frank Lee · Accepted Answer · 2012-06-07T10:03:59

Well, I think your bundle is basically fine, but Felix seems unable to resolve the org.springframework packages, so you need to add some bundle that exports the org.springframework packages. I don't know spring well, but I guess you can download those bundles from springsource.

Maven must have found one too as it seemed to be able to compile it.

How to properly include Spring into an OSGified bundle

2 Answers