diff --git a/redisson/src/main/java/org/redisson/client/handler/PubSubKey.java b/redisson/src/main/java/org/redisson/client/handler/PubSubKey.java
index 306416565..9c8b461fe 100644
--- a/redisson/src/main/java/org/redisson/client/handler/PubSubKey.java
+++ b/redisson/src/main/java/org/redisson/client/handler/PubSubKey.java
@@ -17,6 +17,8 @@ package org.redisson.client.handler;
 
 import org.redisson.client.ChannelName;
 
+import java.util.Objects;
+
 /**
  * 
  * @author Nikita Koksharov
@@ -42,35 +44,15 @@ public class PubSubKey {
     }
 
     @Override
-    @SuppressWarnings("AvoidInlineConditionals")
-    public int hashCode() {
-        final int prime = 31;
-        int result = 1;
-        result = prime * result + ((channel == null) ? 0 : channel.hashCode());
-        result = prime * result + ((operation == null) ? 0 : operation.hashCode());
-        return result;
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+        PubSubKey pubSubKey = (PubSubKey) o;
+        return Objects.equals(channel, pubSubKey.channel) && Objects.equals(operation, pubSubKey.operation);
     }
 
     @Override
-    public boolean equals(Object obj) {
-        if (this == obj)
-            return true;
-        if (obj == null)
-            return false;
-        if (getClass() != obj.getClass())
-            return false;
-        PubSubKey other = (PubSubKey) obj;
-        if (channel == null) {
-            if (other.channel != null)
-                return false;
-        } else if (!channel.equals(other.channel))
-            return false;
-        if (operation == null) {
-            if (other.operation != null)
-                return false;
-        } else if (!operation.equals(other.operation))
-            return false;
-        return true;
+    public int hashCode() {
+        return Objects.hash(channel, operation);
     }
-    
 }
diff --git a/redisson/src/main/java/org/redisson/client/protocol/RedisCommands.java b/redisson/src/main/java/org/redisson/client/protocol/RedisCommands.java
index fb80df8e4..338bf16fc 100644
--- a/redisson/src/main/java/org/redisson/client/protocol/RedisCommands.java
+++ b/redisson/src/main/java/org/redisson/client/protocol/RedisCommands.java
@@ -649,9 +649,9 @@ public interface RedisCommands {
     RedisCommand<Object> PSUBSCRIBE = new RedisCommand<Object>("PSUBSCRIBE", new PubSubStatusDecoder());
     RedisCommand<Object> PUNSUBSCRIBE = new RedisCommand<Object>("PUNSUBSCRIBE", new PubSubStatusDecoder());
 
-    Set<String> PUBSUB_COMMANDS = new HashSet<String>(
+    Set<String> PUBSUB_COMMANDS = Collections.unmodifiableSet(new HashSet<>(
             Arrays.asList(PSUBSCRIBE.getName(), SUBSCRIBE.getName(), PUNSUBSCRIBE.getName(),
-                            UNSUBSCRIBE.getName(), SSUBSCRIBE.getName(), SUNSUBSCRIBE.getName()));
+                    UNSUBSCRIBE.getName(), SSUBSCRIBE.getName(), SUNSUBSCRIBE.getName())));
 
     Set<String> SCAN_COMMANDS = new HashSet<String>(
             Arrays.asList(HSCAN.getName(), SCAN.getName(), ZSCAN.getName(), SSCAN.getName()));