Use restricted class in an OSGi Bundle

问题:

For publishing with SSL using the Endpoint I need to access classes under the packages com.sun.net.httpserver.*

Using the Eclipse IDE I found a way to use this classes. But exporting the bundles and running them in another equinox OSGi Installation I can't start the bundle throwing the following error:

java.lang.NoClassDefFoundError: com/sun/net/httpserver/HttpsConfigurator

Anyone an Idea how to solve this issue?

Thanks!

回答1:

The package you're referring to is part of the JDK. You need to expose it, to make it available in OSGi and you have two options:

The first, and in most cases preferred option, is to expose this package through the system bundle. The OSGi framework has a property that you can set to do this:

org.osgi.framework.system.packages.extra=...

As its value, you provide it with a comma separated list of packages that you want to expose, on top of the ones that are already exposed by the framework. In your case, at least com.sun.net.httpserver, but there might be more packages that you need. In this case, also make sure that the bundle that uses this package imports this package.

The second option is to use a mechanism used boot delegation. It should only be used as a last resort, as it breaks modularity and if it's not used carefully it might lead to other problems. Again, this is a property that you need to set:

org.osgi.framework.bootdelegation=*

Here, you can provide a comma separated list of packages that should be loaded by the boot class loader. Wildcards are supported (as seen in the example above) but you are encouraged to be as specific as possible, so in your case for example use com.sun.* as the value.