Allow primitive array deserializer to be captured by DeserializerModifier (#4219)

Author: JooHyukKim

release-notes/VERSION-2.x

@@ -8,6 +8,12 @@ Project: jackson-databind
 
 -
 
+2.16.1 (not yet released)
+
+#4216: Primitive array deserializer cannot being captured by `DeserializerModifier`
+ (reported by @SakuraKoi)
+ (fix contributed by Joo-Hyuk K)
+
 2.16.0 (15-Nov-2023)
 
 #1770: Incorrect deserialization for `BigDecimal` numbers

src/main/java/com/fasterxml/jackson/databind/deser/BasicDeserializerFactory.java

@@ -1348,13 +1348,15 @@ public JsonDeserializer<?> createArrayDeserializer(DeserializationContext ctxt,
             if (contentDeser == null) {
                 Class<?> raw = elemType.getRawClass();
                 if (elemType.isPrimitive()) {
-                    return PrimitiveArrayDeserializers.forType(raw);
+                    deser = PrimitiveArrayDeserializers.forType(raw);
                 }
                 if (raw == String.class) {
-                    return StringArrayDeserializer.instance;
+                    deser = StringArrayDeserializer.instance;
                 }
             }
-            deser = new ObjectArrayDeserializer(type, contentDeser, elemTypeDeser);
+            if (deser == null) {
+                deser = new ObjectArrayDeserializer(type, contentDeser, elemTypeDeser);
+            }
         }
         // and then new with 2.2: ability to post-process it too (databind#120)
         if (_factoryConfig.hasDeserializerModifiers()) {

src/test/java/com/fasterxml/jackson/databind/deser/BeanDeserializerModifier4216Test.java

@@ -0,0 +1,62 @@
+package com.fasterxml.jackson.databind.deser;
+
+import static com.fasterxml.jackson.databind.BaseMapTest.jsonMapperBuilder;
+import static org.junit.Assert.assertEquals;
+import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.DeserializationConfig;
+import com.fasterxml.jackson.databind.JsonDeserializer;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import com.fasterxml.jackson.databind.type.ArrayType;
+import java.util.concurrent.atomic.AtomicInteger;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Unit test for [databind#4216] : Primitive array deserializer cannot being captured by DeserializerModifier
+ */
+public class BeanDeserializerModifier4216Test
+{
+
+    static class WrapperBean4216 {
+        public Byte[] objArr;
+        public byte[] primArr;
+    }
+
+    @Test
+    public void testModifierCalledTwice() throws Exception
+    {
+        // Given : Configure and construct
+        AtomicInteger counter = new AtomicInteger(0);
+        ObjectMapper objectMapper = jsonMapperBuilder()
+                .addModules(getSimpleModuleWithCounter(counter))
+                .build();
+
+        // Given : Set-up data
+        WrapperBean4216 test = new WrapperBean4216();
+        test.primArr = new byte[]{(byte) 0x11};
+        test.objArr = new Byte[]{(byte) 0x11};
+        String sample = objectMapper.writeValueAsString(test);
+
+        // When
+        objectMapper.readValue(sample, WrapperBean4216.class);
+
+        // Then : modifyArrayDeserializer should be called twice
+        assertEquals(2, counter.get());
+    }
+
+    private static SimpleModule getSimpleModuleWithCounter(AtomicInteger counter) {
+        SimpleModule module = new SimpleModule();
+        module.setDeserializerModifier(
+            new BeanDeserializerModifier() {
+                @Override
+                public JsonDeserializer<?> modifyArrayDeserializer(DeserializationConfig config,
+                        ArrayType valueType, BeanDescription beanDesc, JsonDeserializer<?> deserializer)
+                {
+                    // Count invocations
+                    counter.incrementAndGet();
+                    return deserializer;
+                }
+        });
+        return module;
+    }
+}