OSGi import of package com.ibm.xml.xlxp.api.stax should be resolution:=optional

[wilx]

The XStream core package 1.4.11.1 does not resolve in OSGi environment with Oracle Java. This seems to be because its OSGi manifest is requiring import of package com.ibm.xml.xlxp.api.stax. This appears to be IBM Java specific package, judging from this code in com.thoughtworks.xstream.core.JVM#getStaxInputFactory:

    public static Class<? extends XMLInputFactory> getStaxInputFactory() throws ClassNotFoundException {
        if (isIBM()) {
            return (Class<? extends XMLInputFactory>)Class.forName("com.ibm.xml.xlxp.api.stax.XMLInputFactoryImpl");
        } else {
            return (Class<? extends XMLInputFactory>)Class.forName("com.sun.xml.internal.stream.XMLInputFactoryImpl");
        }
    }

The import should be marked with resolution:=optional:

diff --git a/xstream/pom.xml b/xstream/pom.xml
index e1b0986b..353346a4 100644
--- a/xstream/pom.xml
+++ b/xstream/pom.xml
@@ -394,7 +394,7 @@

   <properties>
     <bundle.export.package>!com.thoughtworks.xstream.core.util,com.thoughtworks.xstream.*;-noimport:=true</bundle.export.package>
-    <bundle.import.package>org.xmlpull.mxp1;resolution:=optional,org.xmlpull.v1;resolution:=optional,*</bundle.import.package>
+    <bundle.import.package>org.xmlpull.mxp1;resolution:=optional,org.xmlpull.v1;resolution:=optional,com.ibm.xml.xlxp.api.stax;resolution:=optional,*</bundle.import.package>
   </properties>

 </project>

[wilx]

Now that I think of it, the com.sun.xml.internal.stream package should be also imported with resolution:=optional so that the OSGi bundle works on AIX with IBM Java.

[joehni]

These are packages of the specific Java runtimes. Why should those be imported?

[wilx]

@joehni I guess that depends OSGi runtime and its setup. Ideally, AFAIK, everything you use should be imported. In any case, the 1.4.11.1 version downloadable from central repository contains OSGi manifest that contains this (I have highlighted the important parts:

Import-Package: org.xmlpull.mxp1;resolution:=optional,org.xmlpull.v1;r
esolution:=optional,com.bea.xml.stream;resolution:=optional,com.ctc.w
stx.stax;resolution:=optional,com.ibm.xml.xlxp.api.stax,com.sun.xml.i
nternal.stream,javax.activation,javax.security.auth,javax.swing,javax

As you can see, both internals of IBM Java and Oracle Java are imported without any qualifiers, so they are hard requirements and the OSGi bundle won't resolve in either Java.

[wilx]

And now that I look closer, I am not sure if sun.misc import is compatible with IBM Java either.

[joehni]

sun.misc is available in any Java runtime ... ;-)

However, I've configured the bundle plugin now to import all classes as optional.