mark nullable

Change-Id: I62f28e98c383dbee8435ce93a10d96118c1463d6

Author: mutianf

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/admin/v2/models/Table.java

@@ -27,6 +27,7 @@
 import java.util.Map;
 import java.util.Map.Entry;
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 import org.threeten.bp.Duration;
 
 /** Wrapper for {@link Table} protocol buffer object */
@@ -144,7 +145,7 @@ public String viewConfig() {
 
   private final Duration changeStreamRetention;
   private final boolean deletionProtection;
-  private final AutomatedBackupPolicy automatedBackupPolicy;
+  @Nullable private final AutomatedBackupPolicy automatedBackupPolicy;
 
   @InternalApi
   public static Table fromProto(@Nonnull com.google.bigtable.admin.v2.Table proto) {
@@ -191,7 +192,7 @@ private Table(
       List<ColumnFamily> columnFamilies,
       Duration changeStreamRetention,
       boolean deletionProtection,
-      AutomatedBackupPolicy automatedBackupPolicy) {
+      @Nullable AutomatedBackupPolicy automatedBackupPolicy) {
     this.instanceId = tableName.getInstance();
     this.id = tableName.getTable();
     this.replicationStatesByClusterId = replicationStatesByClusterId;
@@ -230,10 +231,11 @@ public boolean isDeletionProtected() {
 
   /** Returns whether this table has automated backups enabled. */
   public boolean isAutomatedBackupEnabled() {
-    return automatedBackupPolicy == null ? false : true;
+    return automatedBackupPolicy != null;
   }
 
   /** Returns the automated backup policy config. */
+  @Nullable
   public AutomatedBackupPolicy getAutomatedBackupPolicy() {
     return automatedBackupPolicy;
   }