Merge branch '3.x' into 5405-map-format-shape-bug

Author: cowtowncoder

release-notes/VERSION

@@ -46,6 +46,8 @@ Versions: 3.x (for earlier see VERSION-2.x)
 #5456: Additional configuration (`JsonNodeFeature.STRIP_TRAILING_BIGDECIMAL_ZEROES`: true)
   to MapperBuilder#configureForJackson2 to closer match Jackson 2 behavior
  (contributed by @nrayburn-tech)
+#5475: Support `@JsonDeserializeAs` annotation
+ (implemented by @cowtowncoder, w/ Claude code)
 
 3.0.3 (28-Nov-2025)
 

release-notes/VERSION-2.x

@@ -30,6 +30,10 @@ Project: jackson-databind
  (contributed by Hélios G)
 #5429: Formatting and Parsing of Large ISO-8601 Dates is inconsistent
  (reported by @DavTurns)
+#5475: Support `@JsonDeserializeAs` annotation
+ (implemented by @cowtowncoder, w/ Claude code)
+#5476: Support `@JsonSerializeAs` annotation
+ (implemented by @cowtowncoder, w/ Claude code)
 
 2.20.2 (not yet released)
 

src/main/java/tools/jackson/databind/introspect/JacksonAnnotationIntrospector.java

@@ -36,7 +36,8 @@ public class JacksonAnnotationIntrospector
     @SuppressWarnings("unchecked")
     private final static Class<? extends Annotation>[] ANNOTATIONS_TO_INFER_SER = (Class<? extends Annotation>[])
             new Class<?>[] {
-        JsonSerialize.class,
+        JsonSerialize.class, // databind-specific
+        JsonSerializeAs.class, // since 2.21 alias (and eventual replacement) for `@JsonSerialize.as`
         JsonView.class,
         JsonFormat.class,
         JsonTypeInfo.class,
@@ -49,14 +50,15 @@ public class JacksonAnnotationIntrospector
     @SuppressWarnings("unchecked")
     private final static Class<? extends Annotation>[] ANNOTATIONS_TO_INFER_DESER = (Class<? extends Annotation>[])
             new Class<?>[] {
-        JsonDeserialize.class,
+        JsonDeserialize.class, // databind-specific
+        JsonDeserializeAs.class, // since 2.21 alias (and eventual replacement) for `@JsonDeserialize.as`
         JsonView.class,
         JsonFormat.class,
         JsonTypeInfo.class,
         JsonUnwrapped.class,
         JsonBackReference.class,
         JsonManagedReference.class,
-        JsonMerge.class // since 2.9
+        JsonMerge.class
     };
 
     // NOTE: To avoid mandatory Module dependency to "java.beans", support for 2
@@ -885,10 +887,15 @@ public JavaType refineSerializationType(final MapperConfig<?> config,
         final TypeFactory tf = config.getTypeFactory();
 
         final JsonSerialize jsonSer = _findAnnotation(a, JsonSerialize.class);
+        final JsonSerializeAs jsonSerAs = _findAnnotation(a, JsonSerializeAs.class);
 
         // Ok: start by refining the main type itself; common to all types
 
-        final Class<?> serClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.as());
+        Class<?> serClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.as());
+        // 09-Dec-2025, tatu: [databind#5476] Also check @JsonSerializeAs
+        if (serClass == null && jsonSerAs != null) {
+            serClass = _classIfExplicit(jsonSerAs.value());
+        }
         if (serClass != null) {
             if (type.hasRawClass(serClass)) {
                 // 30-Nov-2015, tatu: As per [databind#1023], need to allow forcing of
@@ -923,7 +930,11 @@ public JavaType refineSerializationType(final MapperConfig<?> config,
         // First, key type (for Maps, Map-like types):
         if (type.isMapLikeType()) {
             JavaType keyType = type.getKeyType();
-            final Class<?> keyClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.keyAs());
+            Class<?> keyClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.keyAs());
+            // 09-Dec-2025, tatu: [databind#5476] Also check @JsonSerializeAs
+            if (keyClass == null && jsonSerAs != null) {
+                keyClass = _classIfExplicit(jsonSerAs.key());
+            }
             if (keyClass != null) {
                 if (keyType.hasRawClass(keyClass)) {
                     keyType = keyType.withStaticTyping();
@@ -958,7 +969,11 @@ public JavaType refineSerializationType(final MapperConfig<?> config,
         JavaType contentType = type.getContentType();
         if (contentType != null) { // collection[like], map[like], array, reference
             // And then value types for all containers:
-           final Class<?> contentClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.contentAs());
+           Class<?> contentClass = (jsonSer == null) ? null : _classIfExplicit(jsonSer.contentAs());
+           // 09-Dec-2025, tatu: [databind#5476] Also check @JsonSerializeAs
+           if (contentClass == null && jsonSerAs != null) {
+               contentClass = _classIfExplicit(jsonSerAs.content());
+           }
            if (contentClass != null) {
                if (contentType.hasRawClass(contentClass)) {
                    contentType = contentType.withStaticTyping();
@@ -1245,9 +1260,14 @@ public JavaType refineDeserializationType(final MapperConfig<?> config,
         final TypeFactory tf = config.getTypeFactory();
 
         final JsonDeserialize jsonDeser = _findAnnotation(a, JsonDeserialize.class);
+        final JsonDeserializeAs jsonDeserAs = _findAnnotation(a, JsonDeserializeAs.class);
 
         // Ok: start by refining the main type itself; common to all types
-        final Class<?> valueClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.as());
+        Class<?> valueClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.as());
+        // 09-Dec-2025, tatu: [databind#5475] Also check @JsonDeserializeAs
+        if (valueClass == null && jsonDeserAs != null) {
+            valueClass = _classIfExplicit(jsonDeserAs.value());
+        }
         if ((valueClass != null) && !type.hasRawClass(valueClass)
                 && !_primitiveAndWrapper(type, valueClass)) {
             try {
@@ -1263,7 +1283,11 @@ public JavaType refineDeserializationType(final MapperConfig<?> config,
         // First, key type (for Maps, Map-like types):
         if (type.isMapLikeType()) {
             JavaType keyType = type.getKeyType();
-            final Class<?> keyClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.keyAs());
+            Class<?> keyClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.keyAs());
+            // 09-Dec-2025, tatu: [databind#5475] Also check @JsonDeserializeAs
+            if (keyClass == null && jsonDeserAs != null) {
+                keyClass = _classIfExplicit(jsonDeserAs.keys());
+            }
             if ((keyClass != null)
                     && !_primitiveAndWrapper(keyType, keyClass)) {
                 try {
@@ -1279,7 +1303,11 @@ public JavaType refineDeserializationType(final MapperConfig<?> config,
         JavaType contentType = type.getContentType();
         if (contentType != null) { // collection[like], map[like], array, reference
             // And then value types for all containers:
-            final Class<?> contentClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.contentAs());
+            Class<?> contentClass = (jsonDeser == null) ? null : _classIfExplicit(jsonDeser.contentAs());
+            // 09-Dec-2025, tatu: [databind#5475] Also check @JsonDeserializeAs
+            if (contentClass == null && jsonDeserAs != null) {
+                contentClass = _classIfExplicit(jsonDeserAs.content());
+            }
             if ((contentClass != null)
                     && !_primitiveAndWrapper(contentType, contentClass)) {
                 try {