Work on writer side of #65

Author: cowtowncoder

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/api/ValueWriter.java

@@ -12,4 +12,18 @@
 public interface ValueWriter {
     public void writeValue(JSONWriter context, JsonGenerator g, Object value)
         throws IOException;
+
+    /*
+    /**********************************************************************
+    /* Minimal metadata
+    /**********************************************************************
+     */
+
+    /**
+     * Accessor for non-generic (type-erased) type of values this reader
+     * produces from input.
+     *
+     * @since 2.10
+     */
+    public Class<?> valueType();
 }

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/BeanWriter.java

@@ -10,7 +10,10 @@ public class BeanWriter
 {
     protected final BeanPropertyWriter[] _properties;
 
-    public BeanWriter(BeanPropertyWriter[] props) {
+    protected final Class<?> _valueType;
+    
+    public BeanWriter(Class<?> type, BeanPropertyWriter[] props) {
+        _valueType = type;
         _properties = props;
     }
 
@@ -21,4 +24,8 @@ public void writeValue(JSONWriter context, JsonGenerator g, Object value)
         context.writeBeanValue(_properties, value);
     }
 
+    @Override
+    public Class<?> valueType() {
+        return _valueType;
+    }
 }

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/JSONWriter.java

@@ -10,6 +10,7 @@
 import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.JSONObjectException;
 import com.fasterxml.jackson.jr.ob.api.ReaderWriterProvider;
+import com.fasterxml.jackson.jr.ob.api.ValueWriter;
 
 import static com.fasterxml.jackson.jr.ob.impl.ValueWriterLocator.*;
 
@@ -268,10 +269,10 @@ public void writeField(String fieldName, Object value, int type) throws IOExcept
         }
 
         if (type < 0) { // Bean type!
-            BeanPropertyWriter[] props = _writerLocator.getPropertyWriters(type);
-            if (props != null) { // sanity check
+            ValueWriter writer = _writerLocator.getValueWriter(type);
+            if (writer != null) { // sanity check
                 _generator.writeFieldName(fieldName);
-                writeBeanValue(props, value);
+                writer.writeValue(this, _generator, value);
                 return;
             }
         }
@@ -382,10 +383,10 @@ protected void _writeValue(Object value, int type) throws IOException
             return;
         }
 
-        if (type < 0) { // Bean type!
-            BeanPropertyWriter[] props = _writerLocator.getPropertyWriters(type);
-            if (props != null) { // sanity check
-                writeBeanValue(props, value);
+        if (type < 0) { // explicit ValueWriter
+            ValueWriter writer = _writerLocator.getValueWriter(type);
+            if (writer != null) { // sanity check
+                writer.writeValue(this, _generator, value);
                 return;
             }
         }

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/ValueWriterLocator.java

@@ -7,6 +7,7 @@
 
 import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.api.ReaderWriterProvider;
+import com.fasterxml.jackson.jr.ob.api.ValueWriter;
 
 /**
  * Helper object used for efficient detection of type information
@@ -36,7 +37,7 @@ public class ValueWriterLocator extends ValueLocatorBase
      */
     protected final ConcurrentHashMap<ClassKey, Integer> _knownSerTypes;
 
-    protected final CopyOnWriteArrayList<BeanPropertyWriter[]> _knownWriters;
+    protected final CopyOnWriteArrayList<ValueWriter> _knownWriters;
 
     /**
      * Provider for custom writers, if any; may be null.
@@ -83,7 +84,7 @@ protected ValueWriterLocator(int features, ReaderWriterProvider rwp)
     {
         _features = features;
         _knownSerTypes = new ConcurrentHashMap<ClassKey, Integer>(20, 0.75f, 2);
-        _knownWriters = new CopyOnWriteArrayList<BeanPropertyWriter[]>();
+        _knownWriters = new CopyOnWriteArrayList<ValueWriter>();
         _writeContext = null;
         _writerProvider = rwp;
     }
@@ -121,7 +122,7 @@ public ValueWriterLocator perOperationInstance(JSONWriter w, int features) {
     /**********************************************************************
      */
 
-    public BeanPropertyWriter[] getPropertyWriters(int index) {
+    public ValueWriter getValueWriter(int index) {
         // for simplicity, let's allow caller to pass negative id as is
         if (index < 0) {
             index = -(index+1);
@@ -180,7 +181,7 @@ protected int _findPOJOSerializationType(Class<?> raw)
                         return I.intValue();
                     }
                     // otherwise add at the end, use -(index+1) as id
-                    _knownWriters.add(props);
+                    _knownWriters.add(new BeanWriter(raw, props));
                     int typeId = -_knownWriters.size();
                     _knownSerTypes.put(k, Integer.valueOf(typeId));
                     return typeId;

release-notes/VERSION-2.x

@@ -7,6 +7,7 @@ Project: jackson-jr
 2.10.0 (not yet released)
 
 #63: Change default for `JSON.Feature.USE_FIELDS` to `true` (from false) in 2.10
+#65: Allow registration of custom readers, writers (to support 3rd party, custom types)
 - Add JDK9+ `module-info.class` using Moditect
 
 2.9.9 (16-May-2019)