Address feedback from @komamitsu

Author: brenbar

msgpack-jackson/src/main/java/org/msgpack/jackson/dataformat/MessagePackFactory.java

@@ -39,6 +39,7 @@ public class MessagePackFactory
     private final MessagePack.PackerConfig packerConfig;
     private boolean reuseResourceInGenerator = true;
     private boolean reuseResourceInParser = true;
+    private boolean writeIntegerKeysAsStringKeys = true;
     private ExtensionTypeCustomDeserializers extTypeCustomDesers;
 
     public MessagePackFactory()
@@ -74,6 +75,12 @@ public MessagePackFactory setReuseResourceInParser(boolean reuseResourceInParser
         return this;
     }
 
+    public MessagePackFactory setWriteIntegerKeysAsStringKeys(boolean writeIntegerKeysAsStringKeys)
+    {
+        this.writeIntegerKeysAsStringKeys = writeIntegerKeysAsStringKeys;
+        return this;
+    }
+
     public MessagePackFactory setExtTypeCustomDesers(ExtensionTypeCustomDeserializers extTypeCustomDesers)
     {
         this.extTypeCustomDesers = extTypeCustomDesers;
@@ -84,7 +91,7 @@ public MessagePackFactory setExtTypeCustomDesers(ExtensionTypeCustomDeserializer
     public JsonGenerator createGenerator(OutputStream out, JsonEncoding enc)
             throws IOException
     {
-        return new MessagePackGenerator(_generatorFeatures, _objectCodec, out, packerConfig, reuseResourceInGenerator);
+        return new MessagePackGenerator(_generatorFeatures, _objectCodec, out, packerConfig, reuseResourceInGenerator, writeIntegerKeysAsStringKeys);
     }
 
     @Override

msgpack-jackson/src/main/java/org/msgpack/jackson/dataformat/MessagePackGenerator.java

@@ -50,6 +50,7 @@ public class MessagePackGenerator
     private static final ThreadLocal<OutputStreamBufferOutput> messageBufferOutputHolder = new ThreadLocal<>();
     private final OutputStream output;
     private final MessagePack.PackerConfig packerConfig;
+    private final boolean writeIntegerKeysAsStringKeys;
 
     private int currentParentElementIndex = -1;
     private int currentState = IN_ROOT;
@@ -195,6 +196,7 @@ private MessagePackGenerator(
         this.messagePacker = packerConfig.newPacker(out);
         this.packerConfig = packerConfig;
         this.nodes = new ArrayList<>();
+        this.writeIntegerKeysAsStringKeys = true;
     }
 
     public MessagePackGenerator(
@@ -210,6 +212,24 @@ public MessagePackGenerator(
         this.messagePacker = packerConfig.newPacker(getMessageBufferOutputForOutputStream(out, reuseResourceInGenerator));
         this.packerConfig = packerConfig;
         this.nodes = new ArrayList<>();
+        this.writeIntegerKeysAsStringKeys = true;
+    }
+
+    public MessagePackGenerator(
+            int features,
+            ObjectCodec codec,
+            OutputStream out,
+            MessagePack.PackerConfig packerConfig,
+            boolean reuseResourceInGenerator,
+            boolean writeIntegerKeysAsStringKeys)
+            throws IOException
+    {
+        super(features, codec);
+        this.output = out;
+        this.messagePacker = packerConfig.newPacker(getMessageBufferOutputForOutputStream(out, reuseResourceInGenerator));
+        this.packerConfig = packerConfig;
+        this.nodes = new ArrayList<>();
+        this.writeIntegerKeysAsStringKeys = writeIntegerKeysAsStringKeys;
     }
 
     private MessageBufferOutput getMessageBufferOutputForOutputStream(
@@ -516,7 +536,12 @@ private void writeByteArrayTextKey(byte[] text, int offset, int len) throws IOEx
     @Override
     public void writeFieldId(long id) throws IOException
     {
-        addKeyNode(id);
+        if (this.writeIntegerKeysAsStringKeys) {
+            super.writeFieldId(id);
+        }
+        else {
+            addKeyNode(id);
+        }
     }
 
     @Override

msgpack-jackson/src/test/java/org/msgpack/jackson/dataformat/MessagePackDataformatForFieldIdTest.java

@@ -87,7 +87,10 @@ protected MapDeserializer withResolved(KeyDeserializer keyDeser, TypeDeserialize
     public void testMixedKeys()
             throws IOException
     {
-        ObjectMapper mapper = new ObjectMapper(new MessagePackFactory())
+        ObjectMapper mapper = new ObjectMapper(
+                    new MessagePackFactory()
+                        .setWriteIntegerKeysAsStringKeys(false)
+                )
                 .registerModule(new SimpleModule()
                 .addDeserializer(Map.class, new MessagePackMapDeserializer()));
 
@@ -103,4 +106,27 @@ public void testMixedKeys()
 
         assertEquals(expected, actual);
     }
+
+    @Test
+    public void testMixedKeysBackwardsCompatiable()
+            throws IOException
+    {
+        ObjectMapper mapper = new ObjectMapper(new MessagePackFactory())
+                .registerModule(new SimpleModule()
+                .addDeserializer(Map.class, new MessagePackMapDeserializer()));
+
+        Map<Object, Object> map = new HashMap<>();
+        map.put(1, "one");
+        map.put("2", "two");
+
+        byte[] bytes = mapper.writeValueAsBytes(map);
+        Map<Object, Object> deserializedInit = mapper.readValue(bytes, new TypeReference<Map<Object, Object>>() {});
+
+        Map<Object, Object> expected = new HashMap<>();
+        expected.put("1", "one");
+        expected.put("2", "two");
+        Map<Object, Object> actual = new HashMap<>(deserializedInit);
+
+        assertEquals(expected, actual);
+    }
 }