Add Connection and refactoring EntityCollection

src/main/kotlin/fr/postgresjson/entity/Entity.kt

@@ -3,11 +3,11 @@ package fr.postgresjson.entity
 import java.util.*
 
 interface EntityI<T> {
-    var id: T
+    var id: T?
 }
-abstract class Entity<T>(override var id: T) : EntityI<T>
-abstract class UuidEntity(override var id: UUID = UUID.randomUUID()) : Entity<UUID>(id)
-abstract class IdEntity(override var id: Int) : Entity<Int>(id)
+abstract class Entity<T>(override var id: T? = null) : EntityI<T?>
+abstract class UuidEntity(override var id: UUID? = UUID.randomUUID()) : Entity<UUID?>(id)
+abstract class IdEntity(override var id: Int? = null) : Entity<Int?>(id)
 
 interface EntityVersioning<T> {
     var version: T

src/main/kotlin/fr/postgresjson/entity/EntityCollection.kt

@@ -1,13 +1,36 @@
 package fr.postgresjson.entity
 
-class EntityCollection<T, E : EntityI<T>> {
-    var collection: MutableMap<T, E> = mutableMapOf()
+import kotlin.reflect.KClass
 
-    fun get(id: T): E? {
-        return collection[id]
+class EntityCollection {
+    val collections: MutableMap<KClass<*>, EntityCollection<Any, EntityI<Any?>>> = mutableMapOf()
+
+    inline fun <I, reified R : EntityI<I?>> get(id: I): R? {
+        val collection = collections[R::class]
+        val entity = collection?.get(id!!)
+        return entity as R?
     }
 
-    fun set(entity: E) {
-        collection.set(entity.id, entity)
+    inline fun <I, reified R : EntityI<I?>> set(entity: R) {
+        if (collections[R::class] == null) {
+            collections[R::class] = EntityCollection()
+        }
+
+        collections[R::class]!!.set(entity as EntityI<Any?>)
+    }
+
+    class EntityCollection<T, E : EntityI<T?>> {
+        private var collection: MutableMap<T, E> = mutableMapOf()
+
+        fun get(id: T): E? {
+            return collection[id]
+        }
+
+        fun set(entity: E) {
+            val id = entity.id
+            if (id !== null) {
+                collection[id] = entity
+            }
+        }
     }
 }