Consolidate entity serialization into one implicit class

[felixmulder]

The templating engine only works on java.util.Map[String, AnyRef] (buuh). This means that for each entity, we must convert it to this format. This is done in: dottydoc.model.JavaConverters.

This file is unnecessarily large, since it contains an implicit class for each subtype of Entity. But! It could be made to just contain one implicit class for all subtypes of Entity. Namely:

implicit class JavaEntity(val ent: Entity) extends AnyVal {
  def asJava: JMap[String, _] = ...
}

The asJava function would return a map with all possible fields of subtypes of Entity with null for value if the field does not exist in the current subtype.

Yes, we hate null in Scala land - but here we are on the border between Java and Scala and as such we have to make some concessions to please the great Java Templating engine gods.

Added bonus points for: getting rid of the _root_ imports, no longer needed

[wutongy]

Hi, @felixmulder. I would like to solve this issue. It would be a good chance for me to familiar with Scala code since I would like to apply for GSOC this year and contribute to Scala community.

[wutongy]

Hi @felixmulder.

Just want to confirm with you if what I try to do is right. Does the one implicit class you suggested look like that? :

implicit class JavaEntity(val ent: Entity) extends AnyVal {
  def asJava(extras: Map[String, _] = Map.empty): JMap[String, _] = ent match {
    case link: MaterializableLink => link match ...
    case ref: Reference =>  ref match ...
    ...
    case _ => null
  }
}

Also, may I ask how to test the code so that I can know my modification is correct and does not break anything by accident? Thanks!

[felixmulder]

This is what I'm suggesting, and the easiest way to test it would be to create an anonymous instance of each entity type. E.g:

// 1. create an instance of each entity kind:
val df = new Def { ... }
val vl = new Val { ... }
// 2. serialize
// 3. run all of the testsssss

A test like this would be unable to compile if the interface changed.