Enabling support for additionalProperties

[Pgarrett]

Adding support for additionalProperties containing objects. If the target DTO contains additionalProperties, then the generated DTO will contain code like:

@JsonIgnore
private val additionalProperties: MutableMap<String, ChildSchema> = mutableMapOf()

@JsonAnyGetter
fun getAdditionalProperties(): MutableMap<String, ChildSchema> {
    return additionalProperties
}

@JsonAnySetter
fun addAdditionalProperty(name: String, value: ChildSchema) {
    additionalProperties[name] = value
}

Where ChildSchema is the nested object represented in the additionalProperties.

[arcuri82]

hmmm... having a lateinit public field that is not initialized on construction (ie in an init{} block) might give issues later on.

[arcuri82]

as a rule of thumb, we should avoid deep nesting. if you have a function, where most/all of its code is inside an if statement, then the condition should be negated and return from function. eg:

if(additionalProperties.isEmpty()) {
   return
}
//rest of the code here

this makes code much easier to read

[arcuri82]

explain in a comment the need for @JsonIgnore here

[arcuri82]

explain in a comment the need for @JsonAnyGetter here

[arcuri82]

this kind of function should be in a utility class, as can be re-used throughout the codebase. for example, before writing something like this, should check what available in org.evomaster.core.utils... there, you can find StringUtils.capitalization() :)