与jdk7和jdk8上的（已更改）doclet API保持兼容

Question

I'm developing a maven plugin that uses the Doclet API ( ConfigurationImpl.getInstance() and HtmlDocletWriter.commentTagsToString() for example). This API is contained in tools.jar that comes with the JDK.

On jdk8, these methods don't exist anymore so the plugin breaks.

I'm now looking for a way to make my plugin work with both jdk7 and 8.

I'm thinking about using an interface that offers a stable API and providing different implementations for each JDK. However, I'm not sure how I can switch/load the correct implementation. Mind that everything needs to be packaged in the same jar (the maven plugin).

Any suggestions?

Answer 1

Create a factory that will give you an instance of your interface. Within the factory you check the java.version system property. If it is >= 8 then you will instantiate the interface implementation for JDK 8, otherwise the one for JDK 7. Those implementation classes must only be loaded in that factory. So you won't get a problem with missing APIs, because the class won't be loaded that depends on that API.