HDDS-2182. Fix checkstyle violations introduced by HDDS-1738

Closes #1529

Author: vivekratnavel

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/bucket/OMBucketDeleteResponse.java

@@ -25,7 +25,6 @@
 import org.apache.hadoop.ozone.protocol.proto.OzoneManagerProtocolProtos;
 import org.apache.hadoop.hdds.utils.db.BatchOperation;
 
-import javax.annotation.Nullable;
 import javax.annotation.Nonnull;
 
 /**

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/key/OMKeyCommitResponse.java

@@ -36,7 +36,8 @@ public class OMKeyCommitResponse extends OMClientResponse {
   private OmKeyInfo omKeyInfo;
   private long openKeySessionID;
 
-  public OMKeyCommitResponse(@Nullable OmKeyInfo omKeyInfo, long openKeySessionID,
+  public OMKeyCommitResponse(@Nullable OmKeyInfo omKeyInfo,
+      long openKeySessionID,
       @Nonnull OzoneManagerProtocolProtos.OMResponse omResponse) {
     super(omResponse);
     this.omKeyInfo = omKeyInfo;

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/key/OMKeyDeleteResponse.java

@@ -38,8 +38,8 @@
 public class OMKeyDeleteResponse extends OMClientResponse {
   private OmKeyInfo omKeyInfo;
 
-
-  public OMKeyDeleteResponse(@Nullable OmKeyInfo omKeyInfo, @Nonnull OMResponse omResponse) {
+  public OMKeyDeleteResponse(@Nullable OmKeyInfo omKeyInfo,
+      @Nonnull OMResponse omResponse) {
     super(omResponse);
     this.omKeyInfo = omKeyInfo;
   }
@@ -69,7 +69,7 @@ public void addToDBBatch(OMMetadataManager omMetadataManager,
         // instance in deletedTable.
         RepeatedOmKeyInfo repeatedOmKeyInfo =
             omMetadataManager.getDeletedTable().get(ozoneKey);
-        if(repeatedOmKeyInfo == null) {
+        if (repeatedOmKeyInfo == null) {
           repeatedOmKeyInfo = new RepeatedOmKeyInfo(omKeyInfo);
         } else {
           repeatedOmKeyInfo.addOmKeyInfo(omKeyInfo);
@@ -83,10 +83,14 @@ public void addToDBBatch(OMMetadataManager omMetadataManager,
   /**
    * Check if the key is empty or not. Key will be empty if it does not have
    * blocks.
+   *
    * @param keyInfo
    * @return if empty true, else false.
    */
   private boolean isKeyEmpty(@Nullable OmKeyInfo keyInfo) {
+    if (keyInfo == null) {
+      return true;
+    }
     for (OmKeyLocationInfoGroup keyLocationList : keyInfo
         .getKeyLocationVersions()) {
       if (keyLocationList.getLocationList().size() != 0) {

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/key/OMKeyPurgeResponse.java

@@ -36,7 +36,8 @@ public class OMKeyPurgeResponse extends OMClientResponse {
 
   private List<String> purgeKeyList;
 
-  public OMKeyPurgeResponse(List<String> keyList, @Nonnull OMResponse omResponse) {
+  public OMKeyPurgeResponse(List<String> keyList,
+      @Nonnull OMResponse omResponse) {
     super(omResponse);
     this.purgeKeyList = keyList;
   }

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/key/OMKeyRenameResponse.java

@@ -39,8 +39,8 @@ public class OMKeyRenameResponse extends OMClientResponse {
   private final String toKeyName;
   private final String fromKeyName;
 
-  public OMKeyRenameResponse(@Nullable OmKeyInfo renameKeyInfo, String toKeyName,
-      String fromKeyName, @Nonnull OMResponse omResponse) {
+  public OMKeyRenameResponse(@Nullable OmKeyInfo renameKeyInfo,
+      String toKeyName, String fromKeyName, @Nonnull OMResponse omResponse) {
     super(omResponse);
     this.renameKeyInfo = renameKeyInfo;
     this.toKeyName = toKeyName;

hadoop-ozone/ozone-manager/src/main/java/org/apache/hadoop/ozone/om/response/s3/multipart/S3MultipartUploadAbortResponse.java

@@ -45,7 +45,8 @@ public class S3MultipartUploadAbortResponse extends OMClientResponse {
   private OmMultipartKeyInfo omMultipartKeyInfo;
 
   public S3MultipartUploadAbortResponse(String multipartKey,
-      @Nullable OmMultipartKeyInfo omMultipartKeyInfo, @Nonnull OMResponse omResponse) {
+      @Nullable OmMultipartKeyInfo omMultipartKeyInfo,
+      @Nonnull OMResponse omResponse) {
     super(omResponse);
     this.multipartKey = multipartKey;
     this.omMultipartKeyInfo = omMultipartKeyInfo;