Refactoring: determine keyComparator at construction time (#161)

* Determine keyComparator at construction time

* Remove ResolvableDeserializer from MaplikeDeserializer

Author: mincong-h

src/main/java/io/vavr/jackson/datatype/deserialize/MapDeserializer.java

@@ -38,11 +38,11 @@ class MapDeserializer extends MaplikeDeserializer<Map<?, ?>> {
 
     MapDeserializer(MapLikeType mapType, KeyDeserializer keyDeserializer, TypeDeserializer elementTypeDeserializer,
                     JsonDeserializer<?> elementDeserializer) {
-        super(mapType, null, keyDeserializer, elementTypeDeserializer, elementDeserializer);
+        super(mapType, keyDeserializer, elementTypeDeserializer, elementDeserializer);
     }
 
     MapDeserializer(MapDeserializer origin, KeyDeserializer keyDeserializer, TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> valueDeserializer) {
-        super(origin.mapType, origin.keyComparator, keyDeserializer, elementTypeDeserializer, valueDeserializer);
+        super(origin.mapType, keyDeserializer, elementTypeDeserializer, valueDeserializer);
     }
 
     @Override
@@ -79,4 +79,5 @@ class MapDeserializer extends MaplikeDeserializer<Map<?, ?>> {
         // default deserialization [...] -> Map
         return HashMap.ofEntries(result);
     }
+
 }

src/main/java/io/vavr/jackson/datatype/deserialize/MaplikeDeserializer.java

@@ -22,35 +22,44 @@
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.deser.ContextualDeserializer;
 import com.fasterxml.jackson.databind.deser.ContextualKeyDeserializer;
-import com.fasterxml.jackson.databind.deser.ResolvableDeserializer;
 import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
 import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
 import com.fasterxml.jackson.databind.type.MapLikeType;
 
 import java.io.Serializable;
 import java.util.Comparator;
 
-abstract class MaplikeDeserializer<T> extends StdDeserializer<T> implements ResolvableDeserializer, ContextualDeserializer {
+abstract class MaplikeDeserializer<T> extends StdDeserializer<T> implements ContextualDeserializer {
 
     private static final long serialVersionUID = 1L;
 
     final MapLikeType mapType;
 
-    Comparator<Object> keyComparator;
+    final Comparator<Object> keyComparator;
     final KeyDeserializer keyDeserializer;
     final TypeDeserializer elementTypeDeserializer;
     final JsonDeserializer<?> elementDeserializer;
 
-    MaplikeDeserializer(MapLikeType mapType, Comparator<Object> keyComparator, KeyDeserializer keyDeserializer,
+    MaplikeDeserializer(MapLikeType mapType, KeyDeserializer keyDeserializer,
                         TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) {
         super(mapType);
         this.mapType = mapType;
-        this.keyComparator = keyComparator;
+        this.keyComparator = createKeyComparator(mapType.getKeyType());
         this.keyDeserializer = keyDeserializer;
         this.elementTypeDeserializer = elementTypeDeserializer;
         this.elementDeserializer = elementDeserializer;
     }
 
+    private Comparator<Object> createKeyComparator(JavaType keyType) {
+        if (Comparable.class.isAssignableFrom(keyType.getRawClass())) {
+            @SuppressWarnings("unchecked")
+            Comparator<Object> comparator = (Comparator<Object> & Serializable) (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);
+            return comparator;
+        } else {
+            return (Comparator<Object> & Serializable) (o1, o2) -> o1.toString().compareTo(o2.toString());
+        }
+    }
+
     /**
      * Creates a new deserializer from the original one (this).
      *
@@ -63,17 +72,6 @@ abstract MaplikeDeserializer<T> createDeserializer(KeyDeserializer keyDeserializ
                                                        TypeDeserializer elementTypeDeserializer,
                                                        JsonDeserializer<?> elementDeserializer);
 
-    @SuppressWarnings("unchecked")
-    @Override
-    public void resolve(DeserializationContext ctxt) throws JsonMappingException {
-        JavaType keyType = mapType.getKeyType();
-        if (Comparable.class.isAssignableFrom(keyType.getRawClass())) {
-            keyComparator = (Comparator<Object> & Serializable) (o1, o2) -> ((Comparable<Object>) o1).compareTo(o2);
-        } else {
-            keyComparator = (Comparator<Object> & Serializable) (o1, o2) -> o1.toString().compareTo(o2.toString());
-        }
-    }
-
     @Override
     public JsonDeserializer<?> createContextual(DeserializationContext context, BeanProperty property) throws JsonMappingException {
         KeyDeserializer keyDeser = keyDeserializer;

src/main/java/io/vavr/jackson/datatype/deserialize/MultimapDeserializer.java

@@ -22,6 +22,7 @@
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.JsonToken;
 import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.deser.ResolvableDeserializer;
 import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
 import com.fasterxml.jackson.databind.type.MapLikeType;
 import io.vavr.Tuple;
@@ -34,20 +35,20 @@
 import java.io.IOException;
 import java.util.ArrayList;
 
-class MultimapDeserializer extends MaplikeDeserializer<Multimap<?, ?>> {
+class MultimapDeserializer extends MaplikeDeserializer<Multimap<?, ?>> implements ResolvableDeserializer {
 
     private static final long serialVersionUID = 1L;
 
     private JsonDeserializer<?> containerDeserializer;
 
     MultimapDeserializer(MapLikeType mapType, KeyDeserializer keyDeserializer, TypeDeserializer elementTypeDeserializer,
                          JsonDeserializer<?> elementDeserializer) {
-        super(mapType, null, keyDeserializer, elementTypeDeserializer, elementDeserializer);
+        super(mapType, keyDeserializer, elementTypeDeserializer, elementDeserializer);
     }
 
     MultimapDeserializer(MultimapDeserializer origin, KeyDeserializer keyDeserializer,
                          TypeDeserializer elementTypeDeserializer, JsonDeserializer<?> elementDeserializer) {
-        super(origin.mapType, origin.keyComparator, keyDeserializer, elementTypeDeserializer, elementDeserializer);
+        super(origin.mapType, keyDeserializer, elementTypeDeserializer, elementDeserializer);
         containerDeserializer = origin.containerDeserializer;
     }
 
@@ -59,7 +60,6 @@ MultimapDeserializer createDeserializer(KeyDeserializer keyDeserializer, TypeDes
 
     @Override
     public void resolve(DeserializationContext ctxt) throws JsonMappingException {
-        super.resolve(ctxt);
         JavaType containerType = ctxt.getTypeFactory().constructCollectionType(ArrayList.class, mapType.getContentType());
         containerDeserializer = ctxt.findContextualValueDeserializer(containerType, null);
     }