Clear collections before pouring in json data. Fixes #75

Author: falkreon

build.gradle

@@ -23,7 +23,7 @@ apply plugin: "signing";
 
 group = "blue.endless";
 archivesBaseName = "Jankson";
-version = "1.2.2";
+version = "1.2.3";
 
 sourceCompatibility = 1.8;
 targetCompatibility = 1.8;

src/main/java/blue/endless/jankson/impl/POJODeserializer.java

@@ -218,8 +218,8 @@ private static boolean isCollections(Class<?> clazz) {
 	public static void unpackMap(Map<Object, Object> map, Type keyType, Type valueType, JsonElement elem, blue.endless.jankson.api.Marshaller marshaller) throws DeserializationException {
 		if (!(elem instanceof JsonObject)) throw new DeserializationException("Cannot deserialize a "+elem.getClass().getSimpleName()+" into a Map - expected a JsonObject!");
 
-		//Class<?> keyClass = TypeMagic.classForType(keyType);
-		//Class<?> valueClass = TypeMagic.classForType(valueType);
+		map.clear(); //This may be a user-supplied collection, initialized in the constructor with default mappings. Erase those.
+		
 		JsonObject object = (JsonObject)elem;
 		for(Map.Entry<String, JsonElement> entry : object.entrySet()) {
 			try {
@@ -233,6 +233,8 @@ public static void unpackMap(Map<Object, Object> map, Type keyType, Type valueTy
 	public static void unpackCollection(Collection<Object> collection, Type elementType, JsonElement elem, blue.endless.jankson.api.Marshaller marshaller) throws DeserializationException {
 		if (!(elem instanceof JsonArray)) throw new DeserializationException("Cannot deserialize a "+elem.getClass().getSimpleName()+" into a Set - expected a JsonArray!");
 
+		collection.clear(); //This may be a user-supplied collection, initialized in the constructor with default items. Erase those.
+		
 		JsonArray array = (JsonArray)elem;
 		for(JsonElement arrayElem : array) {