HDFS-15913. Remove useless NULL checks before instanceof (#2805)

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/BlockStoragePolicy.java

@@ -219,7 +219,7 @@ public class BlockStoragePolicy implements BlockStoragePolicySpi {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof BlockStoragePolicy)) {
+    } else if (!(obj instanceof BlockStoragePolicy)) {
       return false;
     }
     final BlockStoragePolicy that = (BlockStoragePolicy)obj;

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/RollingUpgradeInfo.java

@@ -86,7 +86,7 @@ public class RollingUpgradeInfo extends RollingUpgradeStatus {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof RollingUpgradeInfo)) {
+    } else if (!(obj instanceof RollingUpgradeInfo)) {
       return false;
     }
     final RollingUpgradeInfo that = (RollingUpgradeInfo)obj;

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocol/RollingUpgradeStatus.java

@@ -51,7 +51,7 @@ public class RollingUpgradeStatus {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof RollingUpgradeStatus)) {
+    } else if (!(obj instanceof RollingUpgradeStatus)) {
       return false;
     }
     final RollingUpgradeStatus that = (RollingUpgradeStatus) obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Dispatcher.java

@@ -622,7 +622,7 @@ public class Dispatcher {
       public boolean equals(Object obj) {
         if (this == obj) {
           return true;
-        } else if (obj == null || !(obj instanceof StorageGroup)) {
+        } else if (!(obj instanceof StorageGroup)) {
           return false;
         } else {
           final StorageGroup that = (StorageGroup) obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/blockmanagement/DatanodeStorageInfo.java

@@ -321,7 +321,7 @@ public class DatanodeStorageInfo {
   public boolean equals(Object obj) {
     if (this == obj) {
       return true;
-    } else if (obj == null || !(obj instanceof DatanodeStorageInfo)) {
+    } else if (!(obj instanceof DatanodeStorageInfo)) {
       return false;
     }
     final DatanodeStorageInfo that = (DatanodeStorageInfo)obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ErrorReportAction.java

@@ -68,7 +68,7 @@ public class ErrorReportAction implements BPServiceActorAction {
     if (this == obj) {
       return true;
     }
-    if (obj == null || !(obj instanceof ErrorReportAction)) {
+    if (!(obj instanceof ErrorReportAction)) {
       return false;
     }
     ErrorReportAction other = (ErrorReportAction) obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/ReportBadBlockAction.java

@@ -88,7 +88,7 @@ public class ReportBadBlockAction implements BPServiceActorAction {
     if (this == obj) {
       return true;
     }
-    if (obj == null || !(obj instanceof ReportBadBlockAction)) {
+    if (!(obj instanceof ReportBadBlockAction)) {
       return false;
     }
     ReportBadBlockAction other = (ReportBadBlockAction) obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/StorageLocation.java

@@ -200,7 +200,7 @@ public class StorageLocation
 
   @Override
   public boolean equals(Object obj) {
-    if (obj == null || !(obj instanceof StorageLocation)) {
+    if (!(obj instanceof StorageLocation)) {
       return false;
     }
     int comp = compareTo((StorageLocation) obj);

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/INode.java

@@ -850,7 +850,7 @@ public abstract class INode implements INodeAttributes, Diff.Element<byte[]> {
     if (this == that) {
       return true;
     }
-    if (that == null || !(that instanceof INode)) {
+    if (!(that instanceof INode)) {
       return false;
     }
     return getId() == ((INode) that).getId();

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/QuotaCounts.java

@@ -275,7 +275,7 @@ public class QuotaCounts {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof QuotaCounts)) {
+    } else if (!(obj instanceof QuotaCounts)) {
       return false;
     }
     final QuotaCounts that = (QuotaCounts)obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/Snapshot.java

@@ -232,7 +232,7 @@ public class Snapshot implements Comparable<byte[]> {
   public boolean equals(Object that) {
     if (this == that) {
       return true;
-    } else if (that == null || !(that instanceof Snapshot)) {
+    } else if (!(that instanceof Snapshot)) {
       return false;
     }
     return this.id == ((Snapshot)that).id;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/EnumCounters.java

@@ -130,7 +130,7 @@ public class EnumCounters<E extends Enum<E>> {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof EnumCounters)) {
+    } else if (!(obj instanceof EnumCounters)) {
       return false;
     }
     final EnumCounters<?> that = (EnumCounters<?>)obj;

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/util/EnumDoubles.java

@@ -102,7 +102,7 @@ public class EnumDoubles<E extends Enum<E>> {
   public boolean equals(Object obj) {
     if (obj == this) {
       return true;
-    } else if (obj == null || !(obj instanceof EnumDoubles)) {
+    } else if (!(obj instanceof EnumDoubles)) {
       return false;
     }
     final EnumDoubles<?> that = (EnumDoubles<?>)obj;