feat(jdbc): enable gRPC Keep-Alive for Storage Read API

Author: keshavdandeva

google-cloud-bigquery-jdbc/src/main/java/com/google/cloud/bigquery/jdbc/BigQueryConnection.java

@@ -18,6 +18,7 @@
 
 import com.google.api.gax.core.CredentialsProvider;
 import com.google.api.gax.core.FixedCredentialsProvider;
+import com.google.api.gax.grpc.InstantiatingGrpcChannelProvider;
 import com.google.api.gax.retrying.RetrySettings;
 import com.google.api.gax.rpc.FixedHeaderProvider;
 import com.google.api.gax.rpc.HeaderProvider;
@@ -1053,10 +1054,23 @@ private BigQueryReadClient getBigQueryReadClientConnection() throws IOException
     if (this.universeDomain != null) {
       bigQueryReadSettings.setUniverseDomain(this.universeDomain);
     }
-    if (this.transportChannelProvider != null) {
-      bigQueryReadSettings.setTransportChannelProvider(this.transportChannelProvider);
+    TransportChannelProvider activeProvider = this.transportChannelProvider;
+    if (activeProvider == null) {
+      activeProvider = BigQueryReadSettings.defaultGrpcTransportProviderBuilder().build();
+    }
+
+    if (activeProvider instanceof InstantiatingGrpcChannelProvider) {
+      activeProvider =
+          ((InstantiatingGrpcChannelProvider) activeProvider)
+              .toBuilder()
+                  .setKeepAliveTime(org.threeten.bp.Duration.ofSeconds(10))
+                  .setKeepAliveTimeout(org.threeten.bp.Duration.ofSeconds(5))
+                  .setKeepAliveWithoutCalls(true)
+                  .build();
     }
 
+    bigQueryReadSettings.setTransportChannelProvider(activeProvider);
+
     return BigQueryReadClient.create(bigQueryReadSettings.build());
   }