ScriptEngineManager and ScriptEngine can not be lo

2020-06-22 02:02发布

问题:

I am trying to use ScriptEngineManager and ScriptEngine to execute some JavaScript code with Java. I use Java 8 I am executing this code under Karaf OSGi.

The example I used works fine in a sample Java Class, but packing it in a bundle gives me this error ScriptEngineManager providers.next(): javax.script.ScriptEngineFactory: Provider jdk.nashorn.api.scripting.NashornScriptEngineFactory not found

When I look to the headers of the bundle, I see that the bundle imports javax.script, the package of the called classes but it seems that (nashorn) the provider is not found.

Thanks

回答1:

Go to file etc/config.properties (located inside of Karaf installation), find configuration property org.osgi.framework.bootdelegation and add jdk.nashorn.* to it. Complete configuration will be like this:

org.osgi.framework.bootdelegation=org.apache.karaf.jaas.boot,org.apache.karaf.jaas.boot.principal,sun.*,com.sun.*,javax.transaction,javax.transaction.*,javax.xml.crypto,javax.xml.crypto.*,org.apache.xerces.jaxp.datatype,org.apache.xerces.stax,org.apache.xerces.parsers,org.apache.xerces.jaxp,org.apache.xerces.jaxp.validation,org.apache.xerces.dom,sun.*,jdk.nashorn.*

Bug is reported to Karaf community.

Edit: If you use Pax Exam Container 4.x for Karaf in your tests then don't forget to add org.ops4j.pax.exam.CoreOptions.bootDelegationPackage("jdk.nashorn.*") to the configuration of your test container.



回答2:

You'll need to make sure you have a bundle or the system to actually export those packages in question:

So either install the corresponding bundle, or you need to tweak on the exports of the system bundle, in that case edit the jre.properties and make sure the package in question is exported from the system bundle.