Default mapping for Map and Union; fix TODOs

Author: nbauernfeind

extensions/barrage/src/main/java/io/deephaven/extensions/barrage/util/BarrageUtil.java

@@ -513,8 +513,6 @@ public static BarrageTypeInfo<Field> getDefaultType(@NotNull final Field field)
         }
 
         return new BarrageTypeInfo<>(columnType, columnComponentType, field);
-        // TODO NATE NOCOMMIT
-        // arrowFieldFor(field.getName(), columnType, columnComponentType, field.getMetadata(), false));
     }
 
     private static Class<?> getDefaultType(
@@ -606,7 +604,10 @@ private static Class<?> getDefaultType(
                         throw Exceptions.statusRuntimeException(Code.INVALID_ARGUMENT, exMsg +
                                 " of intervalType(IntervalUnit=" + intervalType.getUnit() + ")");
                 }
-
+            case Map:
+                return Map.class;
+            case Union:
+                return Object.class;
             default:
                 if (arrowField.getType().getTypeID() == ArrowType.ArrowTypeID.List
                         || arrowField.getType().getTypeID() == ArrowType.ArrowTypeID.ListView

server/jetty/src/test/java/io/deephaven/server/jetty/JettyBarrageChunkFactoryTest.java

@@ -1510,8 +1510,8 @@ public void runTest(final TestNullMode nullMode, final TestWrapMode wrapMode) th
 
                 final Field innerField = schema.getFields().get(0);
                 final Map<String, String> attrs = new LinkedHashMap<>(innerField.getMetadata());
-                attrs.put(DH_TYPE_TAG, "java.lang.Object");
-                // TODO NATE NOCOMMIT rm attr?
+                attrs.remove(DH_TYPE_TAG);
+                attrs.remove(DH_COMPONENT_TYPE_TAG);
 
                 final ArrowType unionType = getWrappedModeType(wrapMode,
                         Types.getMinorTypeForArrowType(innerField.getType()));
@@ -1523,8 +1523,8 @@ public void runTest(final TestNullMode nullMode, final TestWrapMode wrapMode) th
 
                 final Field innerField = schema.getFields().get(0);
                 final Map<String, String> attrs = new LinkedHashMap<>(innerField.getMetadata());
-                attrs.put(DH_TYPE_TAG, "java.util.Map");
-                // TODO NATE NOCOMMIT rm attr?
+                attrs.remove(DH_TYPE_TAG);
+                attrs.remove(DH_COMPONENT_TYPE_TAG);
 
                 final ArrowType mapType = new ArrowType.Map(false);