Strange compile error with CacheStore / type wrangling in Scala with Ignite

[Ognen Duzlevski]

Hello,

I am getting a strange compile error when trying to write my own cache
store in Scala:

[error]
/Users/ognen.duzlevski/code/test/src/main/scala/com/ognenduz/test/Cacheable.scala:79:
type mismatch;
[error]  found   :
javax.cache.configuration.Factory[com.ognenduz.test.PostCacheStore]
[error]  required: javax.cache.configuration.Factory[_ <:
org.apache.ignite.cache.store.CacheStore[_ >: K, _ >: V]]
[error]
cacheCfg.setCacheStoreFactory(FactoryBuilder.factoryOf(classOf[PostCacheStore]))

Here is how the below PostCacheStore is set up with the cache configuration:

cacheCfg.setCacheStoreFactory(FactoryBuilder.factoryOf(classOf[PostCacheStore]))

Below is the basic implementation of the cache store for test purposes - it
just writes and reads from elastic search. In addition, note the required
signature for the write() method - the compiler failed and failed until I
fed it the exact signature/syntax - it seems odd that it would have to be
fed exactly that. I am not much of a Java programmer so any help/hints are
appreciated. Thanks!

class PostCacheStore extends CacheStoreAdapter[String,Post] {

  implicit val formats = Serialization.formats(NoTypeHints)

  // get client access to eclipse
  val e = ElasticClient.remote("localhost", 9300)

  // This method is called whenever "get(...)" methods are called on
IgniteCache.
  override def load(key:String):Post = {
    val r = e.execute {
      get id key.toString from "posts"
    }.await
    read[Post](r.getSourceAsString)
  }

  override def write(k:javax.cache.Cache.Entry[_<:String,_<:Post]): Unit = {
    //println("invoking!")
    e.execute({
      index into "posts" source k.getValue
    })
  }

  // FIXME: implement the delete method at some point
  override def delete(k:Any):Unit = {}
}