Remove warnings (#134)

Minor changes for warnings removal.

NamedWriteableRegistryAPI
  remove unused local variables
  remove unused imports

SDKClient
  remove unused private attribute
  remove unsed imports

TransportActions
  add missing diamond operators

TestNamedWriteableRegistryAPI
  remove unused constructor

There are still missing generic declaration on Class<> attributes and
variables, which cannot be fixed only through sdk project, as they are
used as method parameters from classes that do not belong to sdk project
and would require changes on these classes as well.

fix #130

Signed-off-by: Lucas Faria e Souza Vilela <luccasvilela@yahoo.com.br>

Signed-off-by: Lucas Faria e Souza Vilela <luccasvilela@yahoo.com.br>

src/main/java/org/opensearch/sdk/NamedWriteableRegistryAPI.java

@@ -15,17 +15,16 @@
 import java.util.List;
 import java.util.Map;
 
-import org.opensearch.extensions.OpenSearchRequest;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.opensearch.common.io.stream.InputStreamStreamInput;
-import org.opensearch.common.io.stream.NamedWriteable;
 import org.opensearch.common.io.stream.NamedWriteableAwareStreamInput;
 import org.opensearch.common.io.stream.NamedWriteableRegistry;
 import org.opensearch.common.io.stream.NamedWriteableRegistryParseRequest;
-import org.opensearch.extensions.ExtensionBooleanResponse;
 import org.opensearch.common.io.stream.NamedWriteableRegistryResponse;
 import org.opensearch.common.io.stream.StreamInput;
+import org.opensearch.extensions.ExtensionBooleanResponse;
+import org.opensearch.extensions.OpenSearchRequest;
 
 /**
  * API used to handle named writeable registry requests from OpenSearch
@@ -122,7 +121,7 @@ public ExtensionBooleanResponse handleNamedWriteableRegistryParseRequest(NamedWr
                 try {
 
                     // TODO : Determine how extensions utilize parsed object (https://github.com/opensearch-project/OpenSearch/issues/4067)
-                    NamedWriteable namedWriteable = streamInput.readNamedWriteable(categoryClass);
+                    streamInput.readNamedWriteable(categoryClass);
                     status = true;
                 } catch (UnsupportedOperationException e) {
                     logger.info("Failed to parse named writeable", e);

src/main/java/org/opensearch/sdk/SDKClient.java

@@ -10,10 +10,7 @@
 import java.io.IOException;
 
 import org.apache.http.HttpHost;
-
 import org.apache.http.conn.ssl.NoopHostnameVerifier;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
 import org.opensearch.client.RestClient;
 import org.opensearch.client.RestClientBuilder;
 import org.opensearch.client.json.jackson.JacksonJsonpMapper;
@@ -25,7 +22,6 @@
  * This class creates SDKClient for an extension to make requests to OpenSearch
  */
 public class SDKClient {
-    private final Logger logger = LogManager.getLogger(SDKClient.class);
     private OpenSearchClient javaClient;
     private RestClient restClient = null;
 

src/main/java/org/opensearch/sdk/TransportActions.java

@@ -35,7 +35,7 @@ public class TransportActions {
     public <Request extends ActionRequest, Response extends ActionResponse> TransportActions(
         Map<String, Class<? extends TransportAction<Request, Response>>> transportActions
     ) {
-        this.transportActions = new HashMap(transportActions);
+        this.transportActions = new HashMap<>(transportActions);
     }
 
     /**

src/test/java/org/opensearch/sdk/TestNamedWriteableRegistryAPI.java

@@ -45,10 +45,6 @@ private static class Example implements NamedWriteable {
         public static final String NAME = "example";
         private final String message;
 
-        Example(String message) {
-            this.message = message;
-        }
-
         Example(StreamInput in) throws IOException {
             this.message = in.readString();
         }