Fix #1793

Author: cowtowncoder

release-notes/CREDITS

@@ -712,3 +712,8 @@ Luís Cleto (luiscleto@github)
   * Suggested 1768: Improve `TypeFactory.constructFromCanonical()` to work with
    `java.lang.reflect.Type.getTypeName()` format
    (2.9.2)
+
+Vincent Demay (vdemay@github)
+  * Reported #1793: `java.lang.NullPointerException` in `ObjectArraySerializer.acceptJsonFormatVisitor()`
+    for array value with `@JsonValue`
+   (2.9.2)

release-notes/VERSION

@@ -18,6 +18,9 @@ Project: jackson-databind
 #1771: Pass missing argument for string formatting in `ObjectMapper`
  (reported by Nils B)
 #1788: `StdDateFormat._parseAsISO8601()` does not parse "fractional" timezone correctly
+#1793: `java.lang.NullPointerException` in `ObjectArraySerializer.acceptJsonFormatVisitor()`
+  for array value with `@JsonValue`
+ (reported by Vincent D)
 
 2.9.1 (07-Sep-2017)
 

src/main/java/com/fasterxml/jackson/databind/ser/std/JsonValueSerializer.java

@@ -262,7 +262,7 @@ public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType t
                 return;
             }
         }
-        ser.acceptJsonFormatVisitor(visitor, null); 
+        ser.acceptJsonFormatVisitor(visitor, type);
     }
 
     /**

src/main/java/com/fasterxml/jackson/databind/ser/std/ObjectArraySerializer.java

@@ -15,7 +15,6 @@
 import com.fasterxml.jackson.databind.ser.ContainerSerializer;
 import com.fasterxml.jackson.databind.ser.ContextualSerializer;
 import com.fasterxml.jackson.databind.ser.impl.PropertySerializerMap;
-import com.fasterxml.jackson.databind.type.TypeFactory;
 
 /**
  * Generic serializer for Object arrays (<code>Object[]</code>).
@@ -312,12 +311,17 @@ public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType t
     {
         JsonArrayFormatVisitor arrayVisitor = visitor.expectArrayFormat(typeHint);
         if (arrayVisitor != null) {
+            JavaType contentType = _elementType;
+
+            // [databind#1793]: Was getting `null` for `typeHint`. But why would we even use it...
+/*
             TypeFactory tf = visitor.getProvider().getTypeFactory();
-            JavaType contentType = tf.moreSpecificType(_elementType, typeHint.getContentType());
+            contentType = tf.moreSpecificType(_elementType, typeHint.getContentType());
             if (contentType == null) {
                 visitor.getProvider().reportBadDefinition(_elementType,
                         "Could not resolve type: "+_elementType);
             }
+*/
             JsonSerializer<?> valueSer = _elementSerializer;
             if (valueSer == null) {
                 valueSer = visitor.getProvider().findValueSerializer(contentType, _property);

src/test/java/com/fasterxml/jackson/databind/jsonschema/NewSchemaTest.java

@@ -5,6 +5,7 @@
 import java.util.*;
 import java.util.concurrent.atomic.AtomicReference;
 
+import com.fasterxml.jackson.annotation.JsonCreator;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
 import com.fasterxml.jackson.annotation.JsonValue;
 import com.fasterxml.jackson.core.JsonParser.NumberType;
@@ -88,6 +89,17 @@ static class POJOWithRefs {
         public AtomicReference<String> maybeString;
     }
 
+    // [databind#1793]
+    static class POJOWithJsonValue {
+        private Point[] value;
+
+        @JsonCreator(mode=JsonCreator.Mode.DELEGATING)
+        public POJOWithJsonValue(Point[] v) { value = v; }
+
+        @JsonValue
+        public Point[] serialization() { return value; }
+    }
+
     @JsonPropertyOrder({ "dec", "bigInt" })
     static class Numbers {
         public BigDecimal dec;
@@ -206,6 +218,8 @@ public void testBasicTraversal() throws Exception
         MAPPER.acceptJsonFormatVisitor(EnumSet.class, new BogusJsonFormatVisitorWrapper());
 
         MAPPER.acceptJsonFormatVisitor(POJOWithRefs.class, new BogusJsonFormatVisitorWrapper());
+
+        MAPPER.acceptJsonFormatVisitor(POJOWithJsonValue.class, new BogusJsonFormatVisitorWrapper());
     }
 
     public void testSimpleEnum() throws Exception