Use bean context classloader for Jackson

jackson-databind/src/main/java/io/micronaut/jackson/ObjectMapperFactory.java

@@ -32,6 +32,7 @@
 import com.fasterxml.jackson.databind.deser.std.StringDeserializer;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import com.fasterxml.jackson.databind.ser.BeanSerializerModifier;
+import io.micronaut.context.BeanContext;
 import io.micronaut.context.annotation.BootstrapContextCompatible;
 import io.micronaut.context.annotation.Factory;
 import io.micronaut.context.annotation.Primary;
@@ -70,6 +71,9 @@ public class ObjectMapperFactory {
     @Inject
     protected ConversionService conversionService;
 
+    @Inject
+    protected BeanContext beanContext;
+
     @Inject
     // have to be fully qualified due to JDK Module type
     protected com.fasterxml.jackson.databind.Module[] jacksonModules = new com.fasterxml.jackson.databind.Module[0];
@@ -143,6 +147,10 @@ public ObjectMapper objectMapper(@Nullable JacksonConfiguration jacksonConfigura
             objectMapper.findAndRegisterModules();
         }
         objectMapper.registerModules(jacksonModules);
+        if (beanContext != null) {
+            objectMapper.setTypeFactory(objectMapper.getTypeFactory().withClassLoader(beanContext.getClassLoader()));
+        }
+
         SimpleModule module = new SimpleModule(MICRONAUT_MODULE);
         module.setDeserializers(new MicronautDeserializers(conversionService));
 

jackson-databind/src/test/groovy/io/micronaut/jackson/JacksonClassloaderSetupSpec.groovy

@@ -0,0 +1,101 @@
+/*
+ * Copyright 2017-2023 original authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micronaut.jackson
+
+import io.micronaut.annotation.processing.test.AbstractTypeElementSpec
+import io.micronaut.context.ApplicationContext
+import io.micronaut.core.type.Argument
+import io.micronaut.json.JsonMapper
+
+class JacksonClassloaderSetupSpec extends AbstractTypeElementSpec {
+
+    void "test Jackson classloader"() {
+        given:
+            def context = buildContext('test.Animal',"""
+package test;
+
+import com.fasterxml.jackson.annotation.*;
+
+@JsonTypeInfo(use = JsonTypeInfo.Id.MINIMAL_CLASS, defaultImpl = Dog.class)
+interface Animal {
+    String getName();
+}
+
+class Dog implements Animal {
+    private String name;
+    private double barkVolume;
+
+    @Override
+    public String getName() {
+        return name;
+    }
+    public void setName(String name) {
+        this.name = name;
+    }
+    public void setBarkVolume(double barkVolume) {
+        this.barkVolume = barkVolume;
+    }
+    public double getBarkVolume() {
+        return barkVolume;
+    }
+}
+
+class Cat implements Animal {
+    private String name;
+    private int lives;
+    private boolean likesCream;
+    public String getName() {
+        return name;
+    }
+    public void setName(String name) {
+        this.name = name;
+    }
+    public int getLives() {
+        return lives;
+    }
+    public void setLives(int lives) {
+        this.lives = lives;
+    }
+    public void setLikesCream(boolean likesCream) {
+        this.likesCream = likesCream;
+    }
+    public boolean isLikesCream() {
+        return likesCream;
+    }
+}
+""", true)
+
+        when:
+            JsonMapper jsonMapper = context.getBean(JsonMapper)
+
+            def dogBean = jsonMapper.readValue('{"@c":".Dog","name":"Fred","barkVolume":1.1}', argumentOf(context, 'test.Animal'))
+            def catBean = jsonMapper.readValue('{"@c":".Cat","name":"Joe","lives":9,"likesCream":true}', argumentOf(context, 'test.Animal'))
+
+        then:
+            dogBean.name == "Fred"
+            dogBean.barkVolume == 1.1d
+            catBean.name == "Joe"
+            catBean.likesCream
+            catBean.lives == 9
+
+        cleanup:
+            context.close()
+    }
+
+    Argument<Object> argumentOf(ApplicationContext context, String name) {
+        return Argument.of(context.classLoader.loadClass(name))
+    }
+}