Record optional parameters (#542)

Record constructor parameters are optional now

Signed-off-by: David Kral <[email protected]>

Author: Verdent

src/main/java/org/eclipse/yasson/internal/ClassMultiReleaseExtension.java

@@ -36,6 +36,16 @@ static boolean shouldTransformToPropertyName(Method method) {
         return true;
     }
 
+    /**
+     * Whether the class is Record or not.
+     *
+     * @param clazz class to check
+     * @return is record
+     */
+    public static boolean isRecord(Class<?> clazz) {
+        return false;
+    }
+
     static boolean isSpecialAccessorMethod(Method method, Map<String, Property> classProperties) {
         return false;
     }

src/main/java/org/eclipse/yasson/internal/serializer/ObjectDeserializer.java

@@ -15,9 +15,16 @@
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Type;
 import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
+import java.util.OptionalDouble;
+import java.util.OptionalInt;
+import java.util.OptionalLong;
+import java.util.function.Supplier;
 
 import jakarta.json.bind.JsonbException;
 import jakarta.json.bind.serializer.JsonbDeserializer;
@@ -42,6 +49,28 @@
  */
 class ObjectDeserializer<T> extends AbstractContainerDeserializer<T> {
 
+    private static final Map<Class<?>, Supplier<Object>> DEFAULT_CREATOR_VALUES;
+    private static final Supplier<Object> NULL_PROVIDER = () -> null;
+
+    static {
+        Map<Class<?>, Supplier<Object>> tmpValuesMap = new HashMap<>();
+
+        tmpValuesMap.put(byte.class, () -> (byte) 0);
+        tmpValuesMap.put(short.class, () -> (short) 0);
+        tmpValuesMap.put(int.class, () -> 0);
+        tmpValuesMap.put(long.class, () -> 0L);
+        tmpValuesMap.put(float.class, () -> 0.0F);
+        tmpValuesMap.put(double.class, () -> 0.0);
+        tmpValuesMap.put(char.class, () -> '\u0000');
+        tmpValuesMap.put(boolean.class, () -> false);
+        tmpValuesMap.put(Optional.class, Optional::empty);
+        tmpValuesMap.put(OptionalInt.class, OptionalInt::empty);
+        tmpValuesMap.put(OptionalLong.class, OptionalLong::empty);
+        tmpValuesMap.put(OptionalDouble.class, OptionalDouble::empty);
+
+        DEFAULT_CREATOR_VALUES = Collections.unmodifiableMap(tmpValuesMap);
+    }
+
     /**
      * Last property model cache to avoid lookup by jsonKey on every access.
      */
@@ -123,13 +152,18 @@ public T getInstance(Unmarshaller unmarshaller) {
     private T createInstance(Class<T> rawType, JsonbCreator creator) {
         final T instance;
         final List<Object> paramValues = new ArrayList<>();
+        boolean isRecord = ClassMultiReleaseExtension.isRecord(rawType);
         for (CreatorModel param : creator.getParams()) {
             final ValueWrapper valueWrapper = values.get(param.getName());
             //required by spec
-            if (valueWrapper == null) {
+            if (!isRecord && valueWrapper == null) {
                 throw new JsonbException(Messages.getMessage(MessageKeys.JSONB_CREATOR_MISSING_PROPERTY, param.getName()));
+            } else if (valueWrapper == null) {
+                Class<?> rawParamType = ReflectionUtils.getRawType(param.getType());
+                paramValues.add(DEFAULT_CREATOR_VALUES.getOrDefault(rawParamType, NULL_PROVIDER).get());
+            } else {
+                paramValues.add(valueWrapper.getValue());
             }
-            paramValues.add(valueWrapper.getValue());
         }
         instance = creator.call(paramValues.toArray(), rawType);
         return instance;

src/main/java16/org/eclipse/yasson/internal/ClassMultiReleaseExtension.java

@@ -35,7 +35,11 @@ private ClassMultiReleaseExtension() {
     }
 
     static boolean shouldTransformToPropertyName(Method method) {
-        return !method.getDeclaringClass().isRecord();
+        return !isRecord(method.getDeclaringClass());
+    }
+
+    public static boolean isRecord(Class<?> clazz) {
+        return clazz.isRecord();
     }
 
     static boolean isSpecialAccessorMethod(Method method, Map<String, Property> classProperties) {

src/test/java16/org/eclipse/yasson/records/CarCreatorOptionalTest.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2022 Oracle and/or its affiliates. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0,
+ * or the Eclipse Distribution License v. 1.0 which is available at
+ * http://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
+ */
+
+package org.eclipse.yasson.records;
+
+import java.util.Optional;
+
+import jakarta.json.bind.annotation.JsonbCreator;
+import jakarta.json.bind.annotation.JsonbProperty;
+
+public record CarCreatorOptionalTest(String type, int somePrimitive, String color) {
+
+    @JsonbCreator
+    public CarCreatorOptionalTest(@JsonbProperty("type") Optional<String> type,
+                                  @JsonbProperty("somePrimitive") int somePrimitive,
+                                  @JsonbProperty("color") String color) {
+        this(type.orElse("typeDefaultValue"), somePrimitive, color);
+    }
+}

src/test/java16/org/eclipse/yasson/records/RecordTest.java

@@ -94,4 +94,19 @@ public void testRecordJsonbCreator() {
         assertEquals(car, deserialized);
     }
 
+    @Test
+    public void testRecordParameterOptionality() {
+        CarCreatorOptionalTest car = new CarCreatorOptionalTest("skoda", 123, "red");
+        String expected = "{\"color\":\"red\",\"somePrimitive\":123,\"type\":\"skoda\"}";
+
+        String json = Jsonbs.defaultJsonb.toJson(car);
+        assertEquals(expected, json);
+
+        String toDeserialize = "{}";
+        String expectedDefaultValues = "{\"color\":null,\"somePrimitive\":0,\"type\":\"typeDefaultValue\"}";
+        CarCreatorOptionalTest deserialized = Jsonbs.defaultJsonb.fromJson(toDeserialize, CarCreatorOptionalTest.class);
+        json = Jsonbs.nullableJsonb.toJson(deserialized);
+        assertEquals(expectedDefaultValues, json);
+    }
+
 }