Fix #3028

release-notes/VERSION

@@ -41,5 +41,7 @@ Versions: 3.x (for earlier see VERSION-2.x)
   to allow detection of explicitly supported types
 #2713: Change wording of `UnrecognizedPropertyException` to refer to "property" not "field"
 #2828: Add `DatabindException` as intermediate subtype of `JsonMappingException`
+#3028: Change `UUIDSerializer` to use `StreamWriteCapability` check instead of
+  `JsonGenerator.canWriteBinaryNatively()`
 - Remove `MappingJsonFactory`
 - Add context parameter for `TypeSerializer` contextualization (`forProperty()`)

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

@@ -387,7 +387,7 @@ public <T> T readValue(JsonParser p, JavaType type) throws JacksonException {
 
     /*
     /**********************************************************************
-    /* Public API, config setting accessors
+    /* Public API, config feature accessors
     /**********************************************************************
      */
 
@@ -425,16 +425,6 @@ public final boolean hasSomeOfFeatures(int featureMask) {
         return (_featureFlags & featureMask) != 0;
     }
 
-    /**
-     * Method for accessing the currently active parser.
-     * May be different from the outermost parser
-     * when content is buffered.
-     *<p>
-     * Use of this method is discouraged: if code has direct access
-     * to the active parser, that should be used instead.
-     */
-    public final JsonParser getParser() { return _parser; }
-
     /**
      * Accessor for checking whether input format has specified capability
      * or not.
@@ -445,6 +435,22 @@ public final boolean isEnabled(StreamReadCapability cap) {
         return _readCapabilities.isEnabled(cap);
     }
 
+    /*
+    /**********************************************************************
+    /* Public API, accessor for helper objects
+    /**********************************************************************
+     */
+
+    /**
+     * Method for accessing the currently active parser.
+     * May be different from the outermost parser
+     * when content is buffered.
+     *<p>
+     * Use of this method is discouraged: if code has direct access
+     * to the active parser, that should be used instead.
+     */
+    public final JsonParser getParser() { return _parser; }
+
     public final Object findInjectableValue(Object valueId,
             BeanProperty forProperty, Object beanInstance)
     {
@@ -543,7 +549,7 @@ public boolean hasExplicitDeserializerFor(Class<?> valueType) {
 
     /*
     /**********************************************************************
-    /* Public API, CoercionConfig access (2.12+)
+    /* Public API, CoercionConfig access
     /**********************************************************************
      */
 

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

@@ -13,7 +13,7 @@
 import com.fasterxml.jackson.core.io.CharacterEscapes;
 import com.fasterxml.jackson.core.tree.ArrayTreeNode;
 import com.fasterxml.jackson.core.tree.ObjectTreeNode;
-
+import com.fasterxml.jackson.core.util.JacksonFeatureSet;
 import com.fasterxml.jackson.databind.cfg.ContextAttributes;
 import com.fasterxml.jackson.databind.cfg.GeneratorSettings;
 import com.fasterxml.jackson.databind.exc.InvalidDefinitionException;
@@ -88,6 +88,13 @@ public abstract class SerializerProvider
      */
     protected transient JsonGenerator _generator;
 
+    /**
+     * Capabilities of the output format.
+     *
+     * @since 3.0
+     */
+    protected JacksonFeatureSet<StreamWriteCapability> _writeCapabilities;
+
     /**
      * View used for currently active serialization, if any.
      */
@@ -415,7 +422,7 @@ public SerializerProvider setAttribute(Object key, Object value)
 
     /*
     /**********************************************************************
-    /* Access to general configuration
+    /* Access to other on/off features
     /**********************************************************************
      */
 
@@ -438,6 +445,22 @@ public final boolean isEnabled(SerializationFeature feature) {
     public final boolean hasSerializationFeatures(int featureMask) {
         return _config.hasSerializationFeatures(featureMask);
     }
+
+    /**
+     * Accessor for checking whether input format has specified capability
+     * or not.
+     *
+     * @return True if input format has specified capability; false if not
+     */
+    public final boolean isEnabled(StreamWriteCapability cap) {
+        return _writeCapabilities.isEnabled(cap);
+    }
+
+    /*
+    /**********************************************************************
+    /* Access to other helper objects
+    /**********************************************************************
+     */
 
     /**
      * Convenience method for accessing provider to find serialization filters used,

src/main/java/com/fasterxml/jackson/databind/ser/DefaultSerializerProvider.java

@@ -220,7 +220,7 @@ public JsonGenerator getGenerator() {
      */
     public void serializeValue(JsonGenerator gen, Object value) throws JacksonException
     {
-        _generator = gen;
+        _assignGenerator(gen);
         if (value == null) {
             _serializeNull(gen);
             return;
@@ -254,7 +254,7 @@ public void serializeValue(JsonGenerator gen, Object value) throws JacksonExcept
      */
     public void serializeValue(JsonGenerator gen, Object value, JavaType rootType) throws JacksonException
     {
-        _generator = gen;
+        _assignGenerator(gen);
         if (value == null) {
             _serializeNull(gen);
             return;
@@ -291,7 +291,7 @@ public void serializeValue(JsonGenerator gen, Object value, JavaType rootType) t
     public void serializeValue(JsonGenerator gen, Object value, JavaType rootType,
             JsonSerializer<Object> ser) throws JacksonException
     {
-        _generator = gen;
+        _assignGenerator(gen);
         if (value == null) {
             _serializeNull(gen);
             return;
@@ -328,7 +328,7 @@ public void serializePolymorphic(JsonGenerator gen, Object value, JavaType rootT
             JsonSerializer<Object> valueSer, TypeSerializer typeSer)
         throws JacksonException
     {
-        _generator = gen;
+        _assignGenerator(gen);
         if (value == null) {
             _serializeNull(gen);
             return;
@@ -422,6 +422,17 @@ public void acceptJsonFormatVisitor(JavaType javaType, JsonFormatVisitorWrapper
         findRootValueSerializer(javaType).acceptJsonFormatVisitor(visitor, javaType);
     }
 
+    /*
+    /**********************************************************************
+    /* Other helper methods
+    /**********************************************************************
+     */
+
+    private void _assignGenerator(JsonGenerator g) {
+        _generator = g;
+        _writeCapabilities = g.streamWriteCapabilities();
+    }
+
     /*
     /**********************************************************************
     /* Helper classes

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

@@ -4,13 +4,14 @@
 import java.util.UUID;
 
 import com.fasterxml.jackson.annotation.JsonFormat;
+
 import com.fasterxml.jackson.core.JacksonException;
 import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.core.StreamWriteCapability;
 
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonFormatVisitorWrapper;
 import com.fasterxml.jackson.databind.jsonFormatVisitors.JsonValueFormat;
-import com.fasterxml.jackson.databind.util.TokenBuffer;
 
 /**
  * Specialized {@link JsonSerializer} to output {@link java.util.UUID}s.
@@ -73,11 +74,11 @@ public JsonSerializer<?> createContextual(SerializerProvider serializers,
     }
 
     @Override
-    public void serialize(UUID value, JsonGenerator gen, SerializerProvider provider)
+    public void serialize(UUID value, JsonGenerator gen, SerializerProvider ctxt)
         throws JacksonException
     {
         // First: perhaps we could serialize it as raw binary data?
-        if (_writeAsBinary(gen)) {
+        if (_writeAsBinary(ctxt)) {
             gen.writeBinary(_asBytes(value));
             return;
         }
@@ -104,7 +105,7 @@ public void serialize(UUID value, JsonGenerator gen, SerializerProvider provider
         gen.writeString(ch, 0, 36);
     }
 
-    protected boolean _writeAsBinary(JsonGenerator g)
+    protected boolean _writeAsBinary(SerializerProvider ctxt)
     {
         if (_asBinary != null) {
             return _asBinary;
@@ -113,10 +114,11 @@ protected boolean _writeAsBinary(JsonGenerator g)
         //   technically retain binary data, we do not want to do use binary
         //   with it, as that results in UUIDs getting converted to Base64 for
         //   most conversions.
-        return !(g instanceof TokenBuffer) && g.canWriteBinaryNatively();
+        // 28-Jan-2021, tatu: [databind#3028] Use capability detection instead
+//        return !(g instanceof TokenBuffer) && g.canWriteBinaryNatively();
+        return ctxt.isEnabled(StreamWriteCapability.CAN_WRITE_BINARY_NATIVELY);
     }
 
-
     // Need to add bit of extra info, format
     @Override
     public void acceptJsonFormatVisitor(JsonFormatVisitorWrapper visitor, JavaType typeHint)

src/main/java/com/fasterxml/jackson/databind/util/TokenBuffer.java

@@ -654,14 +654,6 @@ public int streamWriteFeatures() {
     /* JsonGenerator implementation: capability introspection
     /**********************************************************************
      */
-
-    /**
-     * Since we can efficiently store <code>byte[]</code>, yes.
-     */
-    @Override
-    public boolean canWriteBinaryNatively() {
-        return true;
-    }
 
     // 20-May-2020, tatu: This may or may not be enough -- ideally access is
     //    via `DeserializationContext`, not parser, but if latter is needed

src/test-jdk14/java/com/fasterxml/jackson/databind/failing/Java9ListsTest.java

@@ -4,8 +4,8 @@
 import java.util.List;
 
 import com.fasterxml.jackson.databind.BaseMapTest;
+import com.fasterxml.jackson.databind.DefaultTyping;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.ObjectMapper.DefaultTyping;
 import com.fasterxml.jackson.databind.json.JsonMapper;
 import com.fasterxml.jackson.databind.testutil.NoCheckSubTypeValidator;