Merge branch 'v2' into eb/v2-initial

# Conflicts:
#	src/main/java/com/launchdarkly/client/dynamodb/DynamoDbFeatureStoreCore.java

Author: eli-darkly

src/main/java/com/launchdarkly/client/dynamodb/DynamoDbFeatureStoreCore.java

@@ -84,17 +84,17 @@ public void close() throws IOException {
   }
 
   @Override
-  public <T extends VersionedData> T getInternal(VersionedDataKind<T> kind, String key) {
+  public VersionedData getInternal(VersionedDataKind<?> kind, String key) {
     GetItemResponse resp = getItemByKeys(namespaceForKind(kind), key);
     return unmarshalItem(kind, resp.item());
   }
 
   @Override
-  public <T extends VersionedData> Map<String, T> getAllInternal(VersionedDataKind<T> kind) {
-    Map<String, T> itemsOut = new HashMap<>();
+  public Map<String, VersionedData> getAllInternal(VersionedDataKind<?> kind) {
+    Map<String, VersionedData> itemsOut = new HashMap<>();
     for (QueryResponse resp: client.queryPaginator(makeQueryForKind(kind).build())) {
       for (Map<String, AttributeValue> item: resp.items()) {
-        T itemOut = unmarshalItem(kind, item);
+        VersionedData itemOut = unmarshalItem(kind, item);
         if (itemOut != null) {
           itemsOut.put(itemOut.getKey(), itemOut);
         }
@@ -104,15 +104,15 @@ public <T extends VersionedData> Map<String, T> getAllInternal(VersionedDataKind
   }
 
   @Override
-  public void initInternal(Map<VersionedDataKind<?>, Map<String, ? extends VersionedData>> allData) {
+  public void initInternal(Map<VersionedDataKind<?>, Map<String, VersionedData>> allData) {
     // Start by reading the existing keys; we will later delete any of these that weren't in allData.
     Set<Map.Entry<String, String>> unusedOldKeys = readExistingKeys(allData.keySet());
 
     List<WriteRequest> requests = new ArrayList<>();
     int numItems = 0;
 
     // Insert or update every provided item
-    for (Map.Entry<VersionedDataKind<?>, Map<String, ? extends VersionedData>> entry: allData.entrySet()) {
+    for (Map.Entry<VersionedDataKind<?>, Map<String, VersionedData>> entry: allData.entrySet()) {
       VersionedDataKind<?> kind = entry.getKey();
       for (VersionedData item: entry.getValue().values()) {       
         Map<String, AttributeValue> encodedItem = marshalItem(kind, item);
@@ -148,7 +148,7 @@ public void initInternal(Map<VersionedDataKind<?>, Map<String, ? extends Version
   }
 
   @Override
-  public <T extends VersionedData> T upsertInternal(VersionedDataKind<T> kind, T item) {
+  public VersionedData upsertInternal(VersionedDataKind<?> kind, VersionedData item) {
     Map<String, AttributeValue> encodedItem = marshalItem(kind, item);
 
     if (updateHook != null) { // instrumentation for tests
@@ -252,7 +252,7 @@ private Map<String, AttributeValue> marshalItem(VersionedDataKind<?> kind, Versi
     );
   }
 
-  private <T extends VersionedData> T unmarshalItem(VersionedDataKind<T> kind, Map<String, AttributeValue> item) {
+  private VersionedData unmarshalItem(VersionedDataKind<?> kind, Map<String, AttributeValue> item) {
     if (item == null || item.size() == 0) {
       return null;
     }