OSGI metadata in MANIFEST.MF is missing 'uses:' information (original) (raw)

When multiple versions of JNA are present in a single OSGI environment, it can happen that OSGI computes an incorrect dependency chain, which can lead to exceptions like the following:

java.lang.LinkageError: loader constraint violation: when resolving interface method 'boolean com.sun.jna.platform.win32.Kernel32.ReadFile(com.sun.jna.platform.win32.WinNT$HANDLE, byte[], int, com.sun.jna.ptr.IntByReference, com.sun.jna.platform.win32.WinBase$OVERLAPPED)' the class loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @216be7ba of the current class, com/sap/adt/sapgui/ui/internal/win32/embedding/PipeHelper, and the class loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @1885dc2b for the method's defining class, com/sun/jna/platform/win32/Kernel32, have different Class objects for the type com/sun/jna/ptr/IntByReference used in the signature (com.sap.adt.sapgui.ui.internal.win32.embedding.PipeHelper is in unnamed module of loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @216be7ba, parent loader 'platform'; com.sun.jna.platform.win32.Kernel32 is in unnamed module of loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @1885dc2b, parent loader 'platform')
    at com.sap.adt.sapgui.ui.internal.win32.embedding.PipeHelper.readNamedPipe(PipeHelper.java:119)
    at com.sap.adt.sapgui.ui.internal.win32.embedding.WinGuiServerProxy$2.run(WinGuiServerProxy.java:133)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

This is a known issue in OSGI when metadata is insufficient and can be addressed by enriching the Export-Package metadata with ;uses="..." information:
https://spring.io/blog/2008/10/20/understanding-the-osgi-uses-directive/

A patch could look like this:

diff --git a/build.xml b/build.xml index 93bad0971..aab63fb33 100644 --- a/build.xml +++ b/build.xml @@ -470,7 +470,7 @@

         <attribute name="Export-Package" value="com.sun.jna;version=${jna.major}.${jna.minor}.${jna.revision}, com.sun.jna.ptr;version=${jna.major}.${jna.minor}.${jna.revision}, com.sun.jna.win32;version=${jna.major}.${jna.minor}.${jna.revision}"/>

         <attribute name="Export-Package" value="com.sun.jna;version=${jna.major}.${jna.minor}.${jna.revision}, com.sun.jna.ptr;version=${jna.major}.${jna.minor}.${jna.revision};uses:=&quot;com.sun.jna&quot;, com.sun.jna.win32;version=${jna.major}.${jna.minor}.${jna.revision};uses:=&quot;com.sun.jna&quot;"/>
         <!-- Note that no terminal "*" is included in this list,
            which will force failure on unsupported platforms.
         -->

diff --git a/contrib/platform/build.xml b/contrib/platform/build.xml index 47fa8ed33..b7f04d393 100644 --- a/contrib/platform/build.xml +++ b/contrib/platform/build.xml @@ -147,20 +147,20 @@

I can open a pull-request to provide a patch.

However, it's a bit fragile to keep maintaining this metadata by hand. A better solution might be to automate the generation of the MANIFEST.MF metadata with bnd:
https://bnd.bndtools.org/