Records should not use default constructor if available (#552)

Records should not use default constructor if available

Signed-off-by: David Kral <david.k.kral@oracle.com>

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

@@ -46,6 +46,10 @@ static JsonbCreator findCreator(Class<?> clazz,
         return null;
     }
 
+    public static boolean isRecord(Class<?> clazz) {
+        return false;
+    }
+
     public static Optional<JsonbException> exceptionToThrow(Class<?> clazz) {
         return Optional.empty();
     }

src/main/java/org/eclipse/yasson/internal/model/ClassModel.java

@@ -23,6 +23,7 @@
 
 import jakarta.json.bind.config.PropertyNamingStrategy;
 
+import org.eclipse.yasson.internal.ClassMultiReleaseExtension;
 import org.eclipse.yasson.internal.ReflectionUtils;
 import org.eclipse.yasson.internal.model.customization.ClassCustomization;
 import org.eclipse.yasson.internal.model.customization.StrategiesProvider;
@@ -190,7 +191,12 @@ public Constructor<?> getDefaultConstructor() {
         // Example: Deserialization into Map won't use this constructor, and therefore never needs to call this method.
         // Note: Null is a valid result and needs to be cached.
         if (!isInitialized.get()) {
-            defaultConstructor = ReflectionUtils.getDefaultConstructor(clazz, false);
+            if (ClassMultiReleaseExtension.isRecord(clazz)) {
+                //No default constructor should be used in case of records
+                defaultConstructor = null;
+            } else {
+                defaultConstructor = ReflectionUtils.getDefaultConstructor(clazz, false);
+            }
             isInitialized.set(true);
         }
         return defaultConstructor;

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

@@ -39,7 +39,7 @@ static boolean shouldTransformToPropertyName(Method method) {
     }
 
     static boolean isSpecialAccessorMethod(Method method, Map<String, Property> classProperties) {
-        return method.getDeclaringClass().isRecord()
+        return isRecord(method.getDeclaringClass())
                 && method.getParameterCount() == 0
                 && !void.class.equals(method.getReturnType())
                 && classProperties.containsKey(method.getName());
@@ -56,6 +56,10 @@ static JsonbCreator findCreator(Class<?> clazz,
         return null;
     }
 
+    public static boolean isRecord(Class<?> clazz) {
+        return clazz.isRecord();
+    }
+
     public static Optional<JsonbException> exceptionToThrow(Class<?> clazz) {
         if (clazz.isRecord()) {
             if (clazz.getDeclaredConstructors().length > 1) {

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

@@ -0,0 +1,21 @@
+/*
+ * 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;
+
+public record CarWithDefaultConstructor(String type, String color) {
+
+    public CarWithDefaultConstructor() {
+        this("some", "other");
+    }
+
+}

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

@@ -96,4 +96,14 @@ public void testRecordJsonbCreator() {
         assertThat(deserialized, is(car));
     }
 
+    @Test
+    public void testRecordWithDefaultConstructor() {
+        CarWithDefaultConstructor car = new CarWithDefaultConstructor("skoda", "red");
+        String expected = "{\"color\":\"red\",\"type\":\"skoda\"}";
+
+        String json = Jsonbs.defaultJsonb.toJson(car);
+        assertThat(json, is(expected));
+        assertThrows(JsonbException.class, () -> Jsonbs.defaultJsonb.fromJson(expected, CarWithDefaultConstructor.class));
+    }
+
 }