Fix FasterXML#898

Author: cowtowncoder

release-notes/VERSION

@@ -14,6 +14,7 @@ Project: jackson-databind
  (reported by Miles K)
 #497: Add new JsonInclude.Include feature to exclude maps after exclusion removes all elements
 #819: Add support for setting `FormatFeature` via `ObjectReader`, `ObjectWriter`
+#898: Add `ObjectMapper.getSerializerProviderInstance()`
 #915: ObjectMapper default timezone is GMT, should be UTC
  (suggested by Infrag@github)
 #918: Add `MapperFeature.ALLOW_EXPLICIT_PROPERTY_RENAMING`

src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java

@@ -1030,18 +1030,38 @@ public SerializerFactory getSerializerFactory() {
     }
 
     /**
-     * Method for setting specific {@link SerializerProvider} to use
-     * for handling caching of {@link JsonSerializer} instances.
+     * Method for setting "blueprint" {@link SerializerProvider} instance
+     * to use as the base for actual provider instances to use for handling
+     * caching of {@link JsonSerializer} instances.
      */
     public ObjectMapper setSerializerProvider(DefaultSerializerProvider p) {
         _serializerProvider = p;
         return this;
     }
 
+    /**
+     * Accessor for the "blueprint" (or, factory) instance, from which instances
+     * are created by calling {@link DefaultSerializerProvider#createInstance}.
+     * Note that returned instance can not be directly used as it is not properly
+     * configured: to get a properly configured instance to call, use
+     * {@link #getSerializerProviderInstance()} instead.
+     */
     public SerializerProvider getSerializerProvider() {
         return _serializerProvider;
     }
 
+    /**
+     * Accessor for constructing and returning a {@link SerializerProvider}
+     * instance that may be used for accessing serializers. This is same as
+     * calling {@link #getSerializerProvider}, and calling <code>createInstance</code>
+     * on it.
+     *
+     * @since 2.7
+     */
+    public SerializerProvider getSerializerProviderInstance() {
+        return _serializerProvider(_serializationConfig);
+    }
+
     /*
     /**********************************************************
     /* Configuration: mix-in annotations
@@ -3429,7 +3449,7 @@ public <T> T convertValue(Object fromValue, JavaType toValueType)
     protected Object _convert(Object fromValue, JavaType toValueType)
         throws IllegalArgumentException
     {        
-        // also, as per [Issue-11], consider case for simple cast
+        // also, as per [databind#11], consider case for simple cast
         /* But with caveats: one is that while everything is Object.class, we don't
          * want to "optimize" that out; and the other is that we also do not want
          * to lose conversions of generic types.

src/main/java/com/fasterxml/jackson/databind/SerializerProvider.java

@@ -235,7 +235,7 @@ protected SerializerProvider(SerializerProvider src,
     /**
      * Copy-constructor used when making a copy of a blueprint instance.
      * 
-     * @since 2.5.0
+     * @since 2.5
      */
     protected SerializerProvider(SerializerProvider src)
     {

src/test/java/com/fasterxml/jackson/databind/ObjectMapperTest.java

@@ -4,9 +4,9 @@
 import java.util.*;
 
 import com.fasterxml.jackson.core.*;
+
 import com.fasterxml.jackson.core.util.MinimalPrettyPrinter;
 
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.deser.DefaultDeserializationContext;
 import com.fasterxml.jackson.databind.introspect.JacksonAnnotationIntrospector;
 import com.fasterxml.jackson.databind.node.*;
@@ -255,12 +255,21 @@ public void testNonSerializabilityOfObject()
     public void testEmptyBeanSerializability()
     {
         // with default settings, error
-        /*
         assertFalse(MAPPER.writer().with(SerializationFeature.FAIL_ON_EMPTY_BEANS)
                 .canSerialize(EmptyBean.class));
-                */
         // but with changes
         assertTrue(MAPPER.writer().without(SerializationFeature.FAIL_ON_EMPTY_BEANS)
                 .canSerialize(EmptyBean.class));
     }
+
+    // for [databind#898]
+    public void testSerializerProviderAccess() throws Exception
+    {
+        // ensure we have "fresh" instance, just in case
+        ObjectMapper mapper = new ObjectMapper();
+        JsonSerializer<?> ser = mapper.getSerializerProviderInstance()
+                .findValueSerializer(Bean.class);
+        assertNotNull(ser);
+        assertEquals(Bean.class, ser.handledType());
+    }
 }