Fix #2324

release-notes/CREDITS-2.x

@@ -842,3 +842,7 @@ Cyril Martin (mcoolive@github.com)
   * Reported #2303: Deserialize null, when java type is "TypeRef of TypeRef of T",
     does not provide "Type(Type(null))"
    (2.9.9)
+
+Daniil Barvitsky (dbarvitsky@github(
+  * Reported #2324: `StringCollectionDeserializer` fails with custom collection
+   (2.9.9)

release-notes/VERSION-2.x

@@ -18,6 +18,8 @@ Project: jackson-databind
  (contributed by Christoph F)
 #2303: Deserialize null, when java type is "TypeRef of TypeRef of T", does not provide "Type(Type(null))"
  (reported by Cyril M)
+#2324: `StringCollectionDeserializer` fails with custom collection
+ (reported byb Daniil B)
 - Prevent String coercion of `null` in `WritableObjectId` when calling `JsonGenerator.writeObjectId()`,
   mostly relevant for formats like YAML that have native Object Ids
 

src/main/java/com/fasterxml/jackson/databind/deser/std/StringCollectionDeserializer.java

@@ -103,8 +103,12 @@ public JsonDeserializer<?> createContextual(DeserializationContext ctxt,
         // May need to resolve types for delegate-based creators:
         JsonDeserializer<Object> delegate = null;
         if (_valueInstantiator != null) {
-            AnnotatedWithParams delegateCreator = _valueInstantiator.getDelegateCreator();
+            // [databind#2324]: check both array-delegating and delegating
+            AnnotatedWithParams delegateCreator = _valueInstantiator.getArrayDelegateCreator();
             if (delegateCreator != null) {
+                JavaType delegateType = _valueInstantiator.getArrayDelegateType(ctxt.getConfig());
+                delegate = findDeserializer(ctxt, delegateType, property);
+            } else if ((delegateCreator = _valueInstantiator.getDelegateCreator()) != null) {
                 JavaType delegateType = _valueInstantiator.getDelegateType(ctxt.getConfig());
                 delegate = findDeserializer(ctxt, delegateType, property);
             }

src/test/java/com/fasterxml/jackson/databind/deser/creators/DelegatingArrayCreator2324Test.java

@@ -0,0 +1,70 @@
+package com.fasterxml.jackson.databind.deser.creators;
+
+import java.util.AbstractCollection;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
+
+import com.fasterxml.jackson.annotation.JsonCreator;
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
+
+// for [databind#2324]
+public class DelegatingArrayCreator2324Test extends BaseMapTest
+{
+    @JsonDeserialize(as=ImmutableBag.class)
+    public interface Bag<T> extends Collection<T> { }
+
+    public static class ImmutableBag<T> extends AbstractCollection<T> implements Bag<T>  {
+        @Override
+        public Iterator<T> iterator() { return elements.iterator(); }
+
+        @Override
+        public int size() { return elements.size(); }
+
+        @JsonCreator(mode=JsonCreator.Mode.DELEGATING)
+        private ImmutableBag(Collection<T> elements ) {
+            this.elements = Collections.unmodifiableCollection(elements);
+        }
+
+        private final Collection<T> elements;
+    }
+
+    static class Value {
+        public String value;
+
+        public Value(String v) { value = v; }
+
+        @Override
+        public boolean equals(Object o) {
+            return value.equals(((Value) o).value);
+        }
+    }
+
+    static class WithBagOfStrings {
+        public Bag<String> getStrings() { return this.bagOfStrings; }
+        public void setStrings(Bag<String> bagOfStrings) { this.bagOfStrings = bagOfStrings; }
+        private Bag<String> bagOfStrings;
+    }
+
+    static class WithBagOfValues {
+        public Bag<Value> getValues() { return this.bagOfValues; }
+        public void setValues(Bag<Value> bagOfValues) { this.bagOfValues = bagOfValues; }
+        private Bag<Value> bagOfValues;
+    }    
+
+    private final ObjectMapper MAPPER = objectMapper();
+
+    public void testDeserializeBagOfStrings() throws Exception {
+        WithBagOfStrings result = MAPPER.readerFor(WithBagOfStrings.class)
+                .readValue("{\"strings\": [ \"a\", \"b\", \"c\"]}");
+        assertEquals(3, result.getStrings().size());
+    }
+
+    public void testDeserializeBagOfPOJOs() throws Exception {
+        WithBagOfValues result = MAPPER.readerFor(WithBagOfValues.class)
+                .readValue("{\"values\": [ \"a\", \"b\", \"c\"]}");
+        assertEquals(3, result.getValues().size());
+        assertEquals(new Value("a"),  result.getValues().iterator().next());
+    }
+}