lib/json_serialization: intro and use a map based on is_same_serialized

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>

diff --git a/lib/json_serialization.nit b/lib/json_serialization.nit
index 4381ad3..69f42bb 100644 (file)
--- a/lib/json_serialization.nit
+++ b/lib/json_serialization.nit
@@ -42,7 +42,7 @@ class JsonSerializer
 
        redef fun serialize_reference(object)
        do
-               if refs_map.keys.has(object) then
+               if refs_map.has_key(object) then
                        # if already serialized, add local reference
                        var id = ref_id_for(object)
                        stream.write "\{\"__kind\": \"ref\", \"__id\": {id}\}"
@@ -53,12 +53,12 @@ class JsonSerializer
        end
 
        # Map of references to already serialized objects.
-       var refs_map = new HashMap[Serializable,Int]
+       private var refs_map = new StrictHashMap[Serializable,Int]
 
        # Get the internal serialized reference for this `object`.
        private fun ref_id_for(object: Serializable): Int
        do
-               if refs_map.keys.has(object) then
+               if refs_map.has_key(object) then
                        return refs_map[object]
                else
                        var id = refs_map.length
@@ -81,8 +81,8 @@ class JsonDeserializer
        # Depth-first path in the serialized object tree.
        var path = new Array[JsonObject]
 
-       # Map of refenrences to already deserialized objects.
-       var id_to_object = new HashMap[Int, Object]
+       # Map of references to already deserialized objects.
+       private var id_to_object = new StrictHashMap[Int, Object]
 
        # Last encountered object reference id.
        #
@@ -128,7 +128,7 @@ class JsonDeserializer
                                var id = object["__id"]
                                assert id isa Int
 
-                               assert id_to_object.keys.has(id)
+                               assert id_to_object.has_key(id)
                                return id_to_object[id]
                        end
 
@@ -142,7 +142,7 @@ class JsonDeserializer
                                var class_name = object["__class"]
                                assert class_name isa String
 
-                               assert not id_to_object.keys.has(id) else print "Error: Object with id '{id}' of {class_name} is deserialized twice."
+                               assert not id_to_object.has_key(id) else print "Error: Object with id '{id}' of {class_name} is deserialized twice."
 
                                # advance on path
                                path.push object
@@ -272,3 +272,59 @@ redef class Array[E]
                end
        end
 end
+
+# Maps instances to a value, uses `is_same_instance`
+#
+# Warning: This class does not implement all the services from `Map`.
+private class StrictHashMap[K, V]
+       super Map[K, V]
+
+       # private
+       var map = new HashMap[K, Array[Couple[K, V]]]
+
+       redef var length = 0
+
+       redef fun is_empty do return length == 0
+
+       # private
+       fun node_at(key: K): nullable Couple[K, V]
+       do
+               if not map.keys.has(key) then return null
+
+               var arr = map[key]
+               for couple in arr do
+                       if couple.first.is_same_serialized(key) then
+                               return couple
+                       end
+               end
+
+               return null
+       end
+
+       redef fun [](key)
+       do
+               var node = node_at(key)
+               assert node != null
+               return node.second
+       end
+
+       redef fun []=(key, value)
+       do
+               var node = node_at(key)
+               if node != null then
+                       node.second = value
+                       return
+               end
+
+               var arr
+               if not map.keys.has(key) then
+                       arr = new Array[Couple[K, V]]
+                       map[key] = arr
+               else arr = map[key]
+
+               arr.add new Couple[K, V](key, value)
+               self.length += 1
+       end
+
+       redef fun has_key(key) do return node_at(key) != null
+end