Implement [JACKSON-764], programmatic way to set root name to use for root-wrapping

8 files changed, 441 insertions, 315 deletions

diff --git a/src/main/java/com/fasterxml/jackson/databind/DeserializationConfig.java b/src/main/java/com/fasterxml/jackson/databind/DeserializationConfig.java
index 9becbacea..90abbd183 100644
--- a/src/main/java/com/fasterxml/jackson/databind/DeserializationConfig.java
+++ b/src/main/java/com/fasterxml/jackson/databind/DeserializationConfig.java
@@ -37,7 +37,7 @@ import com.fasterxml.jackson.databind.util.LinkedNode;
  * with respect to mix-in annotations; where this is guaranteed as
  * long as caller follow "copy-then-use" pattern)
  */
-public class DeserializationConfig
+public final class DeserializationConfig
     extends MapperConfigBase<DeserializationConfig.Feature, DeserializationConfig>
 {
     /**
@@ -334,7 +334,15 @@ public class DeserializationConfig
         _problemHandlers = problemHandlers;
         _nodeFactory = src._nodeFactory;
     }
-       
+
+    private DeserializationConfig(DeserializationConfig src, String rootName)
+    {
+        super(src, rootName);
+        _deserFeatures = src._deserFeatures;
+        _problemHandlers = src._problemHandlers;
+        _nodeFactory = src._nodeFactory;
+    }
+    
     /*
     /**********************************************************
     /* Life-cycle, factory methods from MapperConfig
@@ -365,62 +373,78 @@ public class DeserializationConfig
     
     @Override
     public DeserializationConfig withClassIntrospector(ClassIntrospector<? extends BeanDescription> ci) {
-        return new DeserializationConfig(this, _base.withClassIntrospector(ci));
+        return _withBase(_base.withClassIntrospector(ci));
     }
 
     @Override
     public DeserializationConfig withAnnotationIntrospector(AnnotationIntrospector ai) {
-        return new DeserializationConfig(this, _base.withAnnotationIntrospector(ai));
+        return _withBase(_base.withAnnotationIntrospector(ai));
     }
 
     @Override
     public DeserializationConfig withVisibilityChecker(VisibilityChecker<?> vc) {
-        return new DeserializationConfig(this, _base.withVisibilityChecker(vc));
+        return _withBase(_base.withVisibilityChecker(vc));
     }
 
     @Override
     public DeserializationConfig withVisibility(PropertyAccessor forMethod, JsonAutoDetect.Visibility visibility) {
-        return new DeserializationConfig(this, _base.withVisibility(forMethod, visibility));
+        return _withBase( _base.withVisibility(forMethod, visibility));
     }
     
     @Override
     public DeserializationConfig withTypeResolverBuilder(TypeResolverBuilder<?> trb) {
-        return new DeserializationConfig(this, _base.withTypeResolverBuilder(trb));
+        return _withBase(_base.withTypeResolverBuilder(trb));
     }
 
     @Override
     public DeserializationConfig withSubtypeResolver(SubtypeResolver str) {
-        return new DeserializationConfig(this, str);
+        return (_subtypeResolver == str) ? this : new DeserializationConfig(this, str);
     }
     
     @Override
     public DeserializationConfig withPropertyNamingStrategy(PropertyNamingStrategy pns) {
-        return new DeserializationConfig(this, _base.withPropertyNamingStrategy(pns));
+        return _withBase(_base.withPropertyNamingStrategy(pns));
+    }
+
+    @Override
+    public DeserializationConfig withRootName(String rootName) {
+        if (rootName == null) {
+            if (_rootName == null) {
+                return this;
+            }
+        } else if (rootName.equals(_rootName)) {
+            return this;
+        }
+        return new DeserializationConfig(this, rootName);
     }
     
     @Override
     public DeserializationConfig withTypeFactory(TypeFactory tf) {
-        return (tf == _base.getTypeFactory()) ? this : new DeserializationConfig(this, _base.withTypeFactory(tf));
+        return _withBase( _base.withTypeFactory(tf));
     }
 
     @Override
     public DeserializationConfig withDateFormat(DateFormat df) {
-        return (df == _base.getDateFormat()) ? this : new DeserializationConfig(this, _base.withDateFormat(df));
+        return _withBase(_base.withDateFormat(df));
     }
     
     @Override
     public DeserializationConfig withHandlerInstantiator(HandlerInstantiator hi) {
-        return (hi == _base.getHandlerInstantiator()) ? this : new DeserializationConfig(this, _base.withHandlerInstantiator(hi));
+        return _withBase(_base.withHandlerInstantiator(hi));
     }
 
     @Override
     public DeserializationConfig withInsertedAnnotationIntrospector(AnnotationIntrospector ai) {
-        return new DeserializationConfig(this, _base.withInsertedAnnotationIntrospector(ai));
+        return _withBase(_base.withInsertedAnnotationIntrospector(ai));
     }
 
     @Override
     public DeserializationConfig withAppendedAnnotationIntrospector(AnnotationIntrospector ai) {
-        return new DeserializationConfig(this, _base.withAppendedAnnotationIntrospector(ai));
+        return _withBase(_base.withAppendedAnnotationIntrospector(ai));
+    }
+
+    private final DeserializationConfig _withBase(BaseSettings newBase) {
+        return (_base == newBase) ? this : new DeserializationConfig(this, newBase);
     }
     
     /*
@@ -544,6 +568,15 @@ public class DeserializationConfig
         }
         return NopAnnotationIntrospector.instance;
     }
+
+    @Override
+    public boolean useRootWrapping()
+    {
+        if (_rootName != null) { // empty String disables wrapping; non-empty enables
+            return (_rootName.length() > 0);
+        }
+        return isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE);
+    }
     
     /**
      * Accessor for getting bean description that only contains class
@@ -582,7 +615,7 @@ public class DeserializationConfig
         return vchecker;
     }
 
-    public boolean isEnabled(DeserializationConfig.Feature f) {
+    public final boolean isEnabled(DeserializationConfig.Feature f) {
         return (_deserFeatures & f.getMask()) != 0;
     }
 
diff --git a/src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java b/src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java
index 28dec9155..df86884b7 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ObjectMapper.java
@@ -194,14 +194,12 @@ public class ObjectMapper
     protected final static VisibilityChecker<?> STD_VISIBILITY_CHECKER = VisibilityChecker.Std.defaultInstance();
 
     /**
-     * This is the default {@link DateFormat} used unless overridden by
-     * custom implementation.
+     * Base settings contain defaults used for all {@link ObjectMapper}
+     * instances.
      */
-    protected final static DateFormat DEFAULT_DATE_FORMAT = StdDateFormat.instance;
-
     protected final static BaseSettings DEFAULT_BASE = new BaseSettings(DEFAULT_INTROSPECTOR,
             DEFAULT_ANNOTATION_INTROSPECTOR, STD_VISIBILITY_CHECKER, null, TypeFactory.defaultInstance(),
-            null, DEFAULT_DATE_FORMAT, null);
+            null, StdDateFormat.instance, null);
     
     /*
     /**********************************************************
@@ -353,7 +351,7 @@ public class ObjectMapper
     }
 
     /**
-     * Construct mapper that uses specified {@link JsonFactory}
+     * Constructs instance that uses specified {@link JsonFactory}
      * for constructing necessary {@link JsonParser}s and/or
      * {@link JsonGenerator}s.
      */
@@ -362,25 +360,18 @@ public class ObjectMapper
         this(jf, null, null);
     }
 
-    public ObjectMapper(JsonFactory jf,
-            SerializerProvider sp, DeserializerProvider dp)
-    {
-    	this(jf, sp, dp, null, null);
-    }
-
     /**
+     * Constructs instance that uses specified {@link JsonFactory}
+     * for constructing necessary {@link JsonParser}s and/or
+     * {@link JsonGenerator}s, and uses given providers for accessing
+     * serializers and deserializers.
      * 
      * @param jf JsonFactory to use: if null, a new {@link MappingJsonFactory} will be constructed
      * @param sp SerializerProvider to use: if null, a {@link StdSerializerProvider} will be constructed
      * @param dp DeserializerProvider to use: if null, a {@link StdDeserializerProvider} will be constructed
-     * @param sconfig Serialization configuration to use; if null, basic {@link SerializationConfig}
-     * 	will be constructed
-     * @param dconfig Deserialization configuration to use; if null, basic {@link DeserializationConfig}
-     * 	will be constructed
      */
     public ObjectMapper(JsonFactory jf,
-            SerializerProvider sp, DeserializerProvider dp,
-            SerializationConfig sconfig, DeserializationConfig dconfig)
+            SerializerProvider sp, DeserializerProvider dp)
     {
         /* 02-Mar-2009, tatu: Important: we MUST default to using
          *   the mapping factory, otherwise tree serialization will
@@ -399,11 +390,9 @@ public class ObjectMapper
         _subtypeResolver = new StdSubtypeResolver();
         // and default type factory is shared one
         _typeFactory = TypeFactory.defaultInstance();
-        _serializationConfig = (sconfig != null) ? sconfig :
-            new SerializationConfig(DEFAULT_BASE,
+        _serializationConfig = new SerializationConfig(DEFAULT_BASE,
                     _subtypeResolver, _mixInAnnotations);
-        _deserializationConfig = (dconfig != null) ? dconfig :
-            new DeserializationConfig(DEFAULT_BASE,
+        _deserializationConfig = new DeserializationConfig(DEFAULT_BASE,
                     _subtypeResolver, _mixInAnnotations);
         _serializerProvider = (sp == null) ? new StdSerializerProvider.Impl() : sp;
         _deserializerProvider = (dp == null) ? new StdDeserializerProvider() : dp;
@@ -601,15 +590,6 @@ public class ObjectMapper
     public SerializationConfig getSerializationConfig() {
         return _serializationConfig;
     }
-    
-    /**
-     * Method for replacing the shared default serialization configuration
-     * object.
-     */
-    public ObjectMapper setSerializationConfig(SerializationConfig cfg) {
-        _serializationConfig = cfg;
-        return this;
-    }
 
     /**
      * Method that returns
@@ -622,15 +602,6 @@ public class ObjectMapper
     public DeserializationConfig getDeserializationConfig() {
         return _deserializationConfig;
     }
-
-    /**
-     * Method for replacing the shared default deserialization configuration
-     * object.
-     */
-    public ObjectMapper setDeserializationConfig(DeserializationConfig cfg) {
-        _deserializationConfig = cfg;
-        return this;
-    }
     
     /*
     /**********************************************************
@@ -2660,8 +2631,8 @@ public class ObjectMapper
             DeserializationContext ctxt = _createDeserializationContext(jp, cfg);
             JsonDeserializer<Object> deser = _findRootDeserializer(cfg, valueType);
             // ok, let's get the value
-            if (cfg.isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE)) {
-                result = _unwrapAndDeserialize(jp, valueType, ctxt, deser);
+            if (cfg.useRootWrapping()) {
+                result = _unwrapAndDeserialize(jp, ctxt, cfg, valueType, deser);
             } else {
                 result = deser.deserialize(jp, ctxt);
             }
@@ -2686,8 +2657,8 @@ public class ObjectMapper
                 DeserializationConfig cfg = getDeserializationConfig();
                 DeserializationContext ctxt = _createDeserializationContext(jp, cfg);
                 JsonDeserializer<Object> deser = _findRootDeserializer(cfg, valueType);
-                if (cfg.isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE)) {
-                    result = _unwrapAndDeserialize(jp, valueType, ctxt, deser);
+                if (cfg.useRootWrapping()) {
+                    result = _unwrapAndDeserialize(jp, ctxt, cfg, valueType, deser);
                 } else {
                     result = deser.deserialize(jp, ctxt);
                 }
@@ -2738,32 +2709,36 @@ public class ObjectMapper
         return t;
     }
 
-    protected Object _unwrapAndDeserialize(JsonParser jp, JavaType rootType,
-            DeserializationContext ctxt, JsonDeserializer<Object> deser)
+    protected Object _unwrapAndDeserialize(JsonParser jp, DeserializationContext ctxt, 
+            DeserializationConfig config,
+            JavaType rootType, JsonDeserializer<Object> deser)
         throws IOException, JsonParseException, JsonMappingException
     {
-        SerializedString rootName = _deserializerProvider.findExpectedRootName(ctxt.getConfig(), rootType);
+        String expName = config.getRootName();
+        if (expName == null) {
+            SerializedString sstr = _deserializerProvider.findExpectedRootName(config, rootType);
+            expName = sstr.getValue();
+        }
         if (jp.getCurrentToken() != JsonToken.START_OBJECT) {
             throw JsonMappingException.from(jp, "Current token not START_OBJECT (needed to unwrap root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         if (jp.nextToken() != JsonToken.FIELD_NAME) {
             throw JsonMappingException.from(jp, "Current token not FIELD_NAME (to contain expected root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         String actualName = jp.getCurrentName();
-        if (!rootName.getValue().equals(actualName)) {
-            throw JsonMappingException.from(jp, "Root name '"+actualName+"' does not match expected ('"+rootName
-                    +"') for type "+rootType);
+        if (!expName.equals(actualName)) {
+            throw JsonMappingException.from(jp, "Root name '"+actualName+"' does not match expected ('"
+                    +expName+"') for type "+rootType);
         }
         // ok, then move to value itself....
         jp.nextToken();
-        
         Object result = deser.deserialize(jp, ctxt);
         // and last, verify that we now get matching END_OBJECT
         if (jp.nextToken() != JsonToken.END_OBJECT) {
             throw JsonMappingException.from(jp, "Current token not END_OBJECT (to match wrapper object with root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         return result;
     }
diff --git a/src/main/java/com/fasterxml/jackson/databind/ObjectReader.java b/src/main/java/com/fasterxml/jackson/databind/ObjectReader.java
index ef511ab88..9b5bdd59c 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ObjectReader.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ObjectReader.java
@@ -126,7 +126,7 @@ public class ObjectReader
         }
         _schema = schema;
         _injectableValues = injectableValues;
-        _unwrapRoot = config.isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE);
+        _unwrapRoot = config.useRootWrapping();
     }
     
     /**
@@ -149,7 +149,7 @@ public class ObjectReader
         }
         _schema = schema;
         _injectableValues = injectableValues;
-        _unwrapRoot = config.isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE);
+        _unwrapRoot = config.useRootWrapping();
     }
 
     /**
@@ -167,7 +167,7 @@ public class ObjectReader
         _valueToUpdate = base._valueToUpdate;
         _schema = base._schema;
         _injectableValues = base._injectableValues;
-        _unwrapRoot = config.isEnabled(DeserializationConfig.Feature.UNWRAP_ROOT_VALUE);
+        _unwrapRoot = config.useRootWrapping();
     }
     
     /**
@@ -226,6 +226,68 @@ public class ObjectReader
         DeserializationConfig newConfig = _config.without(first, other);
         return (newConfig == _config) ? this : new ObjectReader(this, newConfig);
     }    
+
+    /**
+     * Method for constructing a new instance with configuration that uses
+     * passed {@link InjectableValues} to provide injectable values.
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
+     */
+    public ObjectReader withInjectableValues(InjectableValues injectableValues)
+    {
+        if (_injectableValues == injectableValues) {
+            return this;
+        }
+        return new ObjectReader(this, _config, _valueType, _valueToUpdate,
+                _schema, injectableValues);
+    }
+
+    /**
+     * Method for constructing a new reader instance with configuration that uses
+     * passed {@link JsonNodeFactory} for constructing {@link JsonNode}
+     * instances.
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
+     */
+    public ObjectReader withNodeFactory(JsonNodeFactory f)
+    {
+        DeserializationConfig newConfig = _config.withNodeFactory(f);
+        return (newConfig == _config) ? this :  new ObjectReader(this, newConfig);
+    }
+
+    /**
+     * Method for constructing a new instance with configuration that
+     * specifies what root name to expect for "root name unwrapping".
+     * See {@link DeserializationConfig#withRootName(String)} for
+     * details.
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
+     */
+    public ObjectReader withRootName(String rootName)
+    {
+        DeserializationConfig newConfig = _config.withRootName(rootName);
+        return (newConfig == _config) ? this :  new ObjectReader(this, newConfig);
+    }
+    
+    /**
+     * Method for constructing a new instance with configuration that
+     * passes specified {@link FormatSchema} to {@link JsonParser} that
+     * is constructed for parsing content.
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
+     */
+    public ObjectReader withSchema(FormatSchema schema)
+    {
+        if (_schema == schema) {
+            return this;
+        }
+        return new ObjectReader(this, _config, _valueType, _valueToUpdate,
+                schema, _injectableValues);
+    }
     
     /**
      * Method for constructing a new reader instance that is configured
@@ -276,22 +338,6 @@ public class ObjectReader
     {
         return withType(_config.getTypeFactory().constructType(valueTypeRef.getType()));
     }    
-    
-    /**
-     * Method for constructing a new reader instance with configuration that uses
-     * passed {@link JsonNodeFactory} for constructing {@link JsonNode}
-     * instances.
-     *<p>
-     * Note that the method does NOT change state of this reader, but
-     * rather construct and returns a newly configured instance.
-     */
-    public ObjectReader withNodeFactory(JsonNodeFactory f)
-    {
-        // node factory is stored within config, so need to copy that first
-        if (f == _config.getNodeFactory()) return this;
-        return new ObjectReader(this, _config.withNodeFactory(f), _valueType, _valueToUpdate,
-                _schema, _injectableValues);
-    }
 
     /**
      * Method for constructing a new instance with configuration that
@@ -311,39 +357,6 @@ public class ObjectReader
         return new ObjectReader(this, _config, t, value,
                 _schema, _injectableValues);
     }    
-
-    /**
-     * Method for constructing a new instance with configuration that
-     * passes specified {@link FormatSchema} to {@link JsonParser} that
-     * is constructed for parsing content.
-     *<p>
-     * Note that the method does NOT change state of this reader, but
-     * rather construct and returns a newly configured instance.
-     */
-    public ObjectReader withSchema(FormatSchema schema)
-    {
-        if (_schema == schema) {
-            return this;
-        }
-        return new ObjectReader(this, _config, _valueType, _valueToUpdate,
-                schema, _injectableValues);
-    }
-
-    /**
-     * Method for constructing a new instance with configuration that uses
-     * passed {@link InjectableValues} to provide injectable values.
-     *<p>
-     * Note that the method does NOT change state of this reader, but
-     * rather construct and returns a newly configured instance.
-     */
-    public ObjectReader withInjectableValues(InjectableValues injectableValues)
-    {
-        if (_injectableValues == injectableValues) {
-            return this;
-        }
-        return new ObjectReader(this, _config, _valueType, _valueToUpdate,
-                _schema, injectableValues);
-    }
     
     /*
     /**********************************************************
@@ -916,19 +929,23 @@ public class ObjectReader
             JavaType rootType, JsonDeserializer<Object> deser)
         throws IOException, JsonParseException, JsonMappingException
     {
-        SerializedString rootName = _provider.findExpectedRootName(ctxt.getConfig(), rootType);
+        String expName = _config.getRootName();
+        if (expName == null) {
+            SerializedString sstr = _provider.findExpectedRootName(_config, rootType);
+            expName = sstr.getValue();
+        }
         if (jp.getCurrentToken() != JsonToken.START_OBJECT) {
             throw JsonMappingException.from(jp, "Current token not START_OBJECT (needed to unwrap root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         if (jp.nextToken() != JsonToken.FIELD_NAME) {
             throw JsonMappingException.from(jp, "Current token not FIELD_NAME (to contain expected root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         String actualName = jp.getCurrentName();
-        if (!rootName.getValue().equals(actualName)) {
-            throw JsonMappingException.from(jp, "Root name '"+actualName+"' does not match expected ('"+rootName
-                    +"') for type "+rootType);
+        if (!expName.equals(actualName)) {
+            throw JsonMappingException.from(jp, "Root name '"+actualName+"' does not match expected ('"
+                    +expName+"') for type "+rootType);
         }
         // ok, then move to value itself....
         jp.nextToken();
@@ -942,7 +959,7 @@ public class ObjectReader
         // and last, verify that we now get matching END_OBJECT
         if (jp.nextToken() != JsonToken.END_OBJECT) {
             throw JsonMappingException.from(jp, "Current token not END_OBJECT (to match wrapper object with root name '"
-                    +rootName+"'), but "+jp.getCurrentToken());
+                    +expName+"'), but "+jp.getCurrentToken());
         }
         return result;
     }
diff --git a/src/main/java/com/fasterxml/jackson/databind/ObjectWriter.java b/src/main/java/com/fasterxml/jackson/databind/ObjectWriter.java
index b7d63fc01..dbe1e4f99 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ObjectWriter.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ObjectWriter.java
@@ -151,8 +151,6 @@ public class ObjectWriter
 
     /**
      * Copy constructor used for building variations.
-     * 
-     * @since 1.7
      */
     protected ObjectWriter(ObjectWriter base, SerializationConfig config)
     {
@@ -223,45 +221,42 @@ public class ObjectWriter
         SerializationConfig newConfig = _config.without(first, other);
         return (newConfig == _config) ? this : new ObjectWriter(this, newConfig);
     }    
-    
+
     /**
-     * Method that will construct a new instance that uses specified
-     * serialization view for serialization (with null basically disables
-     * view processing)
+     * Fluent factory method that will construct a new writer instance that will
+     * use specified date format for serializing dates; or if null passed, one
+     * that will serialize dates as numeric timestamps.
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
      */
-    public ObjectWriter withView(Class<?> view)
+    public ObjectWriter withDateFormat(DateFormat df)
     {
-        if (view == _config.getSerializationView()) return this;
-        return new ObjectWriter(this, _config.withView(view));
-    }    
-    
+        SerializationConfig newConfig = _config.withDateFormat(df);
+        return (newConfig == _config) ? this : new ObjectWriter(this, newConfig);
+    }
+
     /**
-     * Method that will construct a new instance that uses specific type
-     * as the root type for serialization, instead of runtime dynamic
-     * type of the root object itself.
+     * Method that will construct a new instance that will use the default
+     * pretty printer for serialization.
      */
-    public ObjectWriter withType(JavaType rootType)
+    public ObjectWriter withDefaultPrettyPrinter()
     {
-        if (rootType == _rootType) return this;
-        // type is stored here, no need to make a copy of config
-        return new ObjectWriter(this, _config, rootType, _prettyPrinter, _schema);
-    }    
+        return withPrettyPrinter(new DefaultPrettyPrinter());
+    }
 
     /**
-     * Method that will construct a new instance that uses specific type
-     * as the root type for serialization, instead of runtime dynamic
-     * type of the root object itself.
+     * Method that will construct a new instance that uses specified
+     * provider for resolving filter instances by id.
      */
-    public ObjectWriter withType(Class<?> rootType)
+    public ObjectWriter withFilters(FilterProvider filterProvider)
     {
-        return withType(_config.constructType(rootType));
+        if (filterProvider == _config.getFilterProvider()) { // no change?
+            return this;
+        }
+        return new ObjectWriter(this, _config.withFilters(filterProvider));
     }
 
-    public ObjectWriter withType(TypeReference<?> rootType)
-    {
-        return withType(_config.getTypeFactory().constructType(rootType.getType()));
-    }
-    
     /**
      * Method that will construct a new instance that will use specified pretty
      * printer (or, if null, will not do any pretty-printing)
@@ -279,56 +274,74 @@ public class ObjectWriter
     }
 
     /**
-     * Method that will construct a new instance that will use the default
-     * pretty printer for serialization.
-     * 
-     * @since 1.6
+     * Method for constructing a new instance with configuration that
+     * specifies what root name to use for "root element wrapping".
+     * See {@link SerializationConfig#withRootName(String)} for details.
+     *<p>
+     * Note that method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
      */
-    public ObjectWriter withDefaultPrettyPrinter()
+    public ObjectWriter withRootName(String rootName)
     {
-        return withPrettyPrinter(new DefaultPrettyPrinter());
+        SerializationConfig newConfig = _config.withRootName(rootName);
+        return (newConfig == _config) ? this :  new ObjectWriter(this, newConfig);
     }
 
     /**
-     * Method that will construct a new instance that uses specified
-     * provider for resolving filter instances by id.
-     * 
-     * @since 1.7
+     * Method that will construct a new instance that uses specific format schema
+     * for serialization.
+     *<p>
+     * Note that method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
      */
-    public ObjectWriter withFilters(FilterProvider filterProvider)
+    
+    public ObjectWriter withSchema(FormatSchema schema)
     {
-        if (filterProvider == _config.getFilterProvider()) { // no change?
-            return this;
-        }
-        return new ObjectWriter(this, _config.withFilters(filterProvider));
+        return (_schema == schema) ? this :
+            new ObjectWriter(this, _config, _rootType, _prettyPrinter, schema);
     }
-
+    
     /**
-     * @since 1.8
+     * Method that will construct a new instance that uses specific type
+     * as the root type for serialization, instead of runtime dynamic
+     * type of the root object itself.
+     *<p>
+     * Note that method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
      */
-    public ObjectWriter withSchema(FormatSchema schema)
+    public ObjectWriter withType(JavaType rootType)
     {
-        if (_schema == schema) {
-            return this;
-        }
-        return new ObjectWriter(this, _config, _rootType, _prettyPrinter, schema);
+        return (rootType == _rootType) ? this
+        // type is stored here, no need to make a copy of config
+            : new ObjectWriter(this, _config, rootType, _prettyPrinter, _schema);
+    }    
+
+    /**
+     * Method that will construct a new instance that uses specific type
+     * as the root type for serialization, instead of runtime dynamic
+     * type of the root object itself.
+     */
+    public ObjectWriter withType(Class<?> rootType) {
+        return withType(_config.constructType(rootType));
+    }
+
+    public ObjectWriter withType(TypeReference<?> rootType) {
+        return withType(_config.getTypeFactory().constructType(rootType.getType()));
     }
 
     /**
-     * Fluent factory method that will construct a new writer instance that will
-     * use specified date format for serializing dates; or if null passed, one
-     * that will serialize dates as numeric timestamps.
-     * 
-     * @since 1.9
+     * Method that will construct a new instance that uses specified
+     * serialization view for serialization (with null basically disables
+     * view processing)
+     *<p>
+     * Note that the method does NOT change state of this reader, but
+     * rather construct and returns a newly configured instance.
      */
-    public ObjectWriter withDateFormat(DateFormat df)
+    public ObjectWriter withView(Class<?> view)
     {
-        SerializationConfig newConfig = _config.withDateFormat(df);
-        if (newConfig == _config) {
-            return this;
-        }
-        return new ObjectWriter(this, newConfig);
-    }
+        return (view == _config.getSerializationView()) ? this
+            : new ObjectWriter(this, _config.withView(view));
+    }    
     
     /*
     /**********************************************************
diff --git a/src/main/java/com/fasterxml/jackson/databind/SerializationConfig.java b/src/main/java/com/fasterxml/jackson/databind/SerializationConfig.java
index e3cc63244..3c7c6b0a5 100644
--- a/src/main/java/com/fasterxml/jackson/databind/SerializationConfig.java
+++ b/src/main/java/com/fasterxml/jackson/databind/SerializationConfig.java
@@ -5,10 +5,7 @@ import java.util.*;
 
 import com.fasterxml.jackson.annotation.*;
 import com.fasterxml.jackson.annotation.JsonAutoDetect.Visibility;
-import com.fasterxml.jackson.databind.cfg.BaseSettings;
-import com.fasterxml.jackson.databind.cfg.ConfigFeature;
-import com.fasterxml.jackson.databind.cfg.MapperConfig;
-import com.fasterxml.jackson.databind.cfg.MapperConfigBase;
+import com.fasterxml.jackson.databind.cfg.*;
 import com.fasterxml.jackson.databind.introspect.Annotated;
 import com.fasterxml.jackson.databind.introspect.ClassIntrospector;
 import com.fasterxml.jackson.databind.introspect.VisibilityChecker;
@@ -32,7 +29,7 @@ import com.fasterxml.jackson.databind.util.ClassUtil;
  * with respect to mix-in annotations; where this is guaranteed as
  * long as caller follow "copy-then-use" pattern)
  */
-public class SerializationConfig
+public final class SerializationConfig
     extends MapperConfigBase<SerializationConfig.Feature, SerializationConfig>
 {
     /**
@@ -384,6 +381,15 @@ public class SerializationConfig
         _serializationView = src._serializationView;
         _filterProvider = src._filterProvider;
     }
+
+    private SerializationConfig(SerializationConfig src, String rootName)
+    {
+        super(src, rootName);
+        _serFeatures = src._serFeatures;
+        _serializationInclusion = src._serializationInclusion;
+        _serializationView = src._serializationView;
+        _filterProvider = src._filterProvider;
+    }
     
     /*
     /**********************************************************
@@ -465,6 +471,18 @@ public class SerializationConfig
     public SerializationConfig withPropertyNamingStrategy(PropertyNamingStrategy pns) {
         return _withBase(_base.withPropertyNamingStrategy(pns));
     }
+
+    @Override
+    public SerializationConfig withRootName(String rootName) {
+        if (rootName == null) {
+            if (_rootName == null) {
+                return this;
+            }
+        } else if (rootName.equals(_rootName)) {
+            return this;
+        }
+        return new SerializationConfig(this, rootName);
+    }
     
     @Override
     public SerializationConfig withTypeFactory(TypeFactory tf) {
@@ -577,6 +595,15 @@ public class SerializationConfig
     }
     
     @Override
+    public boolean useRootWrapping()
+    {
+        if (_rootName != null) { // empty String disables wrapping; non-empty enables
+            return (_rootName.length() > 0);
+        }
+        return isEnabled(SerializationConfig.Feature.WRAP_ROOT_VALUE);
+    }
+    
+    @Override
     public AnnotationIntrospector getAnnotationIntrospector()
     {
         /* 29-Jul-2009, tatu: it's now possible to disable use of
diff --git a/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfig.java b/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfig.java
index 5a34dc037..b5fb47c53 100644
--- a/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfig.java
+++ b/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfig.java
@@ -313,7 +313,6 @@ public abstract class MapperConfig<T extends MapperConfig<T>>
         }
         return flags;
     }
-    
     /*
     /**********************************************************
     /* Life-cycle: factory methods
@@ -332,116 +331,6 @@ public abstract class MapperConfig<T extends MapperConfig<T>>
      */
     public abstract T without(MapperConfig.Feature... features);
     
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link ClassIntrospector}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withClassIntrospector(ClassIntrospector<? extends BeanDescription> ci);
-
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link AnnotationIntrospector} to use (replacing old one).
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withAnnotationIntrospector(AnnotationIntrospector ai);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link VisibilityChecker}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withVisibilityChecker(VisibilityChecker<?> vc);
-
-    /**
-     * Method for constructing and returning a new instance with different
-     * minimal visibility level for specified property type
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withVisibility(PropertyAccessor forMethod, JsonAutoDetect.Visibility visibility);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link TypeResolverBuilder}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withTypeResolverBuilder(TypeResolverBuilder<?> trb);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link SubtypeResolver}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withSubtypeResolver(SubtypeResolver str);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link PropertyNamingStrategy}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withPropertyNamingStrategy(PropertyNamingStrategy strategy);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link TypeFactory}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withTypeFactory(TypeFactory typeFactory);
-    
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link DateFormat}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withDateFormat(DateFormat df);
-
-    /**
-     * Method for constructing and returning a new instance with different
-     * {@link HandlerInstantiator}
-     * to use.
-     *<p>
-     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
-     * if directly calling this method.
-     */
-    public abstract T withHandlerInstantiator(HandlerInstantiator hi);
-
-    /**
-     * Method for constructing and returning a new instance with additional
-     * {@link AnnotationIntrospector} inserted (as the highest priority one)
-     */
-    public abstract T withInsertedAnnotationIntrospector(AnnotationIntrospector introspector);
-
-    /**
-     * Method for constructing and returning a new instance with additional
-     * {@link AnnotationIntrospector} appended (as the lowest priority one)
-     */
-    public abstract T withAppendedAnnotationIntrospector(AnnotationIntrospector introspector);
-    
     /*
     /**********************************************************
     /* Configuration: simple features
@@ -488,6 +377,13 @@ public abstract class MapperConfig<T extends MapperConfig<T>>
     public final boolean shouldSortPropertiesAlphabetically() {
         return isEnabled(MapperConfig.Feature.SORT_PROPERTIES_ALPHABETICALLY);
     }
+
+    /**
+     * Accessor for checking whether configuration indicates that
+     * "root wrapping" (use of an extra property/name pair at root level)
+     * is expected or not.
+     */
+    public abstract boolean useRootWrapping();
     
     /*
     /**********************************************************
diff --git a/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfigBase.java b/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfigBase.java
index 2dfafd0d6..79add3375 100644
--- a/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfigBase.java
+++ b/src/main/java/com/fasterxml/jackson/databind/cfg/MapperConfigBase.java
@@ -1,9 +1,20 @@
 package com.fasterxml.jackson.databind.cfg;
 
+import java.text.DateFormat;
 import java.util.Map;
 
+import com.fasterxml.jackson.annotation.JsonAutoDetect;
+import com.fasterxml.jackson.annotation.PropertyAccessor;
+import com.fasterxml.jackson.databind.AnnotationIntrospector;
+import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.HandlerInstantiator;
+import com.fasterxml.jackson.databind.PropertyNamingStrategy;
+import com.fasterxml.jackson.databind.introspect.ClassIntrospector;
+import com.fasterxml.jackson.databind.introspect.VisibilityChecker;
 import com.fasterxml.jackson.databind.jsontype.SubtypeResolver;
+import com.fasterxml.jackson.databind.jsontype.TypeResolverBuilder;
 import com.fasterxml.jackson.databind.type.ClassKey;
+import com.fasterxml.jackson.databind.type.TypeFactory;
 
 public abstract class MapperConfigBase<CFG extends ConfigFeature,
     T extends MapperConfigBase<CFG,T>>
@@ -28,6 +39,13 @@ public abstract class MapperConfigBase<CFG extends ConfigFeature,
      * in addition to) ones declared using annotations.
      */
     protected final SubtypeResolver _subtypeResolver;
+
+    /**
+     * Explicitly definite root name to use, if any; if empty
+     * String, will disable root-name wrapping; if null, will
+     * use defaults
+     */
+    protected final String _rootName;
     
     /*
     /**********************************************************
@@ -45,6 +63,7 @@ public abstract class MapperConfigBase<CFG extends ConfigFeature,
         super(base, DEFAULT_MAPPER_FEATURES);
         _mixInAnnotations = mixins;
         _subtypeResolver = str;
+        _rootName = null;
     }
     
     /**
@@ -55,6 +74,15 @@ public abstract class MapperConfigBase<CFG extends ConfigFeature,
         super(src);
         _mixInAnnotations = src._mixInAnnotations;
         _subtypeResolver = src._subtypeResolver;
+        _rootName = src._rootName;
+    }
+
+    protected MapperConfigBase(MapperConfigBase<CFG,T> src, BaseSettings base)
+    {
+        super(base, src._mapperFeatures);
+        _mixInAnnotations = src._mixInAnnotations;
+        _subtypeResolver = src._subtypeResolver;
+        _rootName = src._rootName;
     }
     
     protected MapperConfigBase(MapperConfigBase<CFG,T> src, int mapperFeatures)
@@ -62,21 +90,142 @@ public abstract class MapperConfigBase<CFG extends ConfigFeature,
         super(src._base, mapperFeatures);
         _mixInAnnotations = src._mixInAnnotations;
         _subtypeResolver = src._subtypeResolver;
+        _rootName = src._rootName;
     }
 
     protected MapperConfigBase(MapperConfigBase<CFG,T> src, SubtypeResolver str) {
         super(src);
         _mixInAnnotations = src._mixInAnnotations;
         _subtypeResolver = str;
+        _rootName = src._rootName;
     }
 
-    protected MapperConfigBase(MapperConfigBase<CFG,T> src, BaseSettings base)
-    {
-        super(base, src._mapperFeatures);
+    protected MapperConfigBase(MapperConfigBase<CFG,T> src, String rootName) {
+        super(src);
         _mixInAnnotations = src._mixInAnnotations;
         _subtypeResolver = src._subtypeResolver;
+        _rootName = rootName;
     }
+    
+    /*
+    /**********************************************************
+    /* Addition fluent factory methods, common to all sub-types
+    /**********************************************************
+     */
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link AnnotationIntrospector} to use (replacing old one).
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withAnnotationIntrospector(AnnotationIntrospector ai);
+
+    /**
+     * Method for constructing and returning a new instance with additional
+     * {@link AnnotationIntrospector} appended (as the lowest priority one)
+     */
+    public abstract T withAppendedAnnotationIntrospector(AnnotationIntrospector introspector);
+
+    /**
+     * Method for constructing and returning a new instance with additional
+     * {@link AnnotationIntrospector} inserted (as the highest priority one)
+     */
+    public abstract T withInsertedAnnotationIntrospector(AnnotationIntrospector introspector);
+    
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link ClassIntrospector}
+     * to use.
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withClassIntrospector(ClassIntrospector<? extends BeanDescription> ci);
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link DateFormat}
+     * to use.
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withDateFormat(DateFormat df);
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link HandlerInstantiator}
+     * to use.
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withHandlerInstantiator(HandlerInstantiator hi);
+    
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link PropertyNamingStrategy}
+     * to use.
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withPropertyNamingStrategy(PropertyNamingStrategy strategy);
+    
+    /**
+     * Method for constructing and returning a new instance with different
+     * root name to use (none, if null).
+     *<p>
+     * Note that when a root name is set to a non-Empty String, this will automatically force use
+     * of root element wrapping with given name. If empty String passed, will
+     * disable root name wrapping; and if null used, will instead use
+     * <code>Feature</code> to determine if to use wrapping, and annotation
+     * (or default name) for actual root name to use.
+     * 
+     * @param rootName to use: if null, means "use default" (clear setting);
+     *   if empty String ("") means that no root name wrapping is used;
+     *   otherwise defines root name to use.
+     */
+    public abstract T withRootName(String rootName);
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link SubtypeResolver}
+     * to use.
+     *<p>
+     * NOTE: make sure to register new instance with <code>ObjectMapper</code>
+     * if directly calling this method.
+     */
+    public abstract T withSubtypeResolver(SubtypeResolver str);
+    
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link TypeFactory}
+     * to use.
+     */
+    public abstract T withTypeFactory(TypeFactory typeFactory);
 
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link TypeResolverBuilder} to use.
+     */
+    public abstract T withTypeResolverBuilder(TypeResolverBuilder<?> trb);
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * {@link VisibilityChecker}
+     * to use.
+     */
+    public abstract T withVisibilityChecker(VisibilityChecker<?> vc);
+
+    /**
+     * Method for constructing and returning a new instance with different
+     * minimal visibility level for specified property type
+     */
+    public abstract T withVisibility(PropertyAccessor forMethod, JsonAutoDetect.Visibility visibility);
+    
     /*
     /**********************************************************
     /* Simple accessors
@@ -93,6 +242,10 @@ public abstract class MapperConfigBase<CFG extends ConfigFeature,
     public final SubtypeResolver getSubtypeResolver() {
         return _subtypeResolver;
     }
+
+    public final String getRootName() {
+        return _rootName;
+    }
     
     /*
     /**********************************************************
diff --git a/src/main/java/com/fasterxml/jackson/databind/ser/StdSerializerProvider.java b/src/main/java/com/fasterxml/jackson/databind/ser/StdSerializerProvider.java
index 4dc6f86d7..4eeb46b55 100644
--- a/src/main/java/com/fasterxml/jackson/databind/ser/StdSerializerProvider.java
+++ b/src/main/java/com/fasterxml/jackson/databind/ser/StdSerializerProvider.java
@@ -570,7 +570,7 @@ public abstract class StdSerializerProvider
      * Method called on the actual non-blueprint provider instance object,
      * to kick off the serialization.
      */
-    protected  void _serializeValue(JsonGenerator jgen, Object value)
+    protected final void _serializeValue(JsonGenerator jgen, Object value)
         throws IOException, JsonProcessingException
     {
         JsonSerializer<Object> ser;
@@ -584,11 +584,23 @@ public abstract class StdSerializerProvider
             Class<?> cls = value.getClass();
             // true, since we do want to cache root-level typed serializers (ditto for null property)
             ser = findTypedValueSerializer(cls, true, null);
-            // [JACKSON-163]
-            wrap = _config.isEnabled(SerializationConfig.Feature.WRAP_ROOT_VALUE);
-            if (wrap) {
+
+            // Ok: should we wrap result in an additional property ("root name")?
+            String rootName = _config.getRootName();
+            if (rootName == null) { // not explicitly specified
+                // [JACKSON-163]
+                wrap = _config.isEnabled(SerializationConfig.Feature.WRAP_ROOT_VALUE);
+                if (wrap) {
+                    jgen.writeStartObject();
+                    jgen.writeFieldName(_rootNames.findRootName(value.getClass(), _config));
+                }
+            } else if (rootName.length() == 0) {
+                wrap = false;
+            } else { // [JACKSON-764]
+                // empty String means explicitly disabled; non-empty that it is enabled
+                wrap = true;
                 jgen.writeStartObject();
-                jgen.writeFieldName(_rootNames.findRootName(value.getClass(), _config));
+                jgen.writeFieldName(rootName);
             }
         }
         try {