Fixed NPE in RedissonSession #1971

redisson-tomcat/redisson-tomcat-6/src/main/java/org/redisson/tomcat/RedissonSession.java

@@ -60,7 +60,7 @@ public class RedissonSession extends StandardSession {
     private final RedissonSessionManager.ReadMode readMode;
     private final UpdateMode updateMode;
     
-    private Set<String> removedAttributes;
+    private Set<String> removedAttributes = Collections.emptySet();
     
     public RedissonSession(RedissonSessionManager manager, ReadMode readMode, UpdateMode updateMode) {
         super(manager);

redisson-tomcat/redisson-tomcat-7/src/main/java/org/redisson/tomcat/RedissonSession.java

@@ -60,7 +60,7 @@ public class RedissonSession extends StandardSession {
     private final RedissonSessionManager.ReadMode readMode;
     private final UpdateMode updateMode;
     
-    private Set<String> removedAttributes;
+    private Set<String> removedAttributes = Collections.emptySet();
     
     public RedissonSession(RedissonSessionManager manager, RedissonSessionManager.ReadMode readMode, UpdateMode updateMode) {
         super(manager);

redisson-tomcat/redisson-tomcat-8/src/main/java/org/redisson/tomcat/RedissonSession.java

@@ -60,7 +60,7 @@ public class RedissonSession extends StandardSession {
     private final RedissonSessionManager.ReadMode readMode;
     private final UpdateMode updateMode;
     
-    private Set<String> removedAttributes;
+    private Set<String> removedAttributes = Collections.emptySet();
     
     public RedissonSession(RedissonSessionManager manager, RedissonSessionManager.ReadMode readMode, UpdateMode updateMode) {
         super(manager);

redisson-tomcat/redisson-tomcat-9/src/main/java/org/redisson/tomcat/RedissonSession.java

@@ -60,7 +60,7 @@ public class RedissonSession extends StandardSession {
     private final RedissonSessionManager.ReadMode readMode;
     private final UpdateMode updateMode;
     
-    private Set<String> removedAttributes;
+    private Set<String> removedAttributes = Collections.emptySet();
     
     public RedissonSession(RedissonSessionManager manager, RedissonSessionManager.ReadMode readMode, UpdateMode updateMode) {
         super(manager);