avoid mutable state

Signed-off-by: tison <wander4096@gmail.com>

curator-framework/src/main/java/org/apache/curator/framework/imps/GetConfigBuilderImpl.java

@@ -33,7 +33,6 @@
 public class GetConfigBuilderImpl
         implements GetConfigBuilder, BackgroundOperation<Void>, ErrorListenerEnsembleable<byte[]> {
     private final CuratorFrameworkImpl client;
-    private final WatcherRemovalManager watcherRemovalManager;
 
     private Backgrounding backgrounding;
     private Watching watching;
@@ -45,14 +44,8 @@ public GetConfigBuilderImpl(CuratorFrameworkImpl client) {
 
     public GetConfigBuilderImpl(CuratorFrameworkImpl client, Backgrounding backgrounding, Watcher watcher, Stat stat) {
         this.client = (CuratorFrameworkImpl) client.usingNamespace(null);
-        this.watcherRemovalManager = client.getWatcherRemovalManager();
         this.backgrounding = backgrounding;
-        // We are using `client.usingNamespace(null)` to avoid `unfixNamespace` for "/zookeeper/config"(CURATOR-667)
-        // events. But `client.usingNamespace(null)` will loss possible `WatcherRemovalManager`(CURATOR-710). So, let's
-        // reset it.
-        //
-        // See also `NamespaceWatchedEvent`.
-        this.watching = new Watching(this.client, watcher).setWatcherRemovalManager(watcherRemovalManager);
+        this.watching = new Watching(this.client, watcher);
         this.stat = stat;
     }
 
@@ -115,19 +108,19 @@ public BackgroundEnsembleable<byte[]> usingWatcher(CuratorWatcher watcher) {
 
     @Override
     public BackgroundEnsembleable<byte[]> watched() {
-        watching = new Watching(client, true).setWatcherRemovalManager(watcherRemovalManager);
+        watching = new Watching(client, true);
         return new InternalBackgroundEnsembleable();
     }
 
     @Override
     public BackgroundEnsembleable<byte[]> usingWatcher(Watcher watcher) {
-        watching = new Watching(client, watcher).setWatcherRemovalManager(watcherRemovalManager);
+        watching = new Watching(client, watcher);
         return new InternalBackgroundEnsembleable();
     }
 
     @Override
     public BackgroundEnsembleable<byte[]> usingWatcher(CuratorWatcher watcher) {
-        watching = new Watching(client, watcher).setWatcherRemovalManager(watcherRemovalManager);
+        watching = new Watching(client, watcher);
         return new InternalBackgroundEnsembleable();
     }
 

curator-framework/src/main/java/org/apache/curator/framework/imps/WatcherRemovalFacade.java

@@ -37,9 +37,13 @@ class WatcherRemovalFacade extends CuratorFrameworkImpl implements WatcherRemove
     private final WatcherRemovalManager removalManager;
 
     WatcherRemovalFacade(CuratorFrameworkImpl client) {
+        this(client, new WatcherRemovalManager(client));
+    }
+
+    private WatcherRemovalFacade(CuratorFrameworkImpl client, WatcherRemovalManager removalManager) {
         super(client);
         this.client = client;
-        removalManager = new WatcherRemovalManager(client);
+        this.removalManager = removalManager;
     }
 
     @Override
@@ -73,7 +77,8 @@ public CuratorFramework nonNamespaceView() {
 
     @Override
     public CuratorFramework usingNamespace(String newNamespace) {
-        return client.usingNamespace(newNamespace);
+        final CuratorFrameworkImpl newClient = (CuratorFrameworkImpl) client.usingNamespace(newNamespace);
+        return new WatcherRemovalFacade(newClient, removalManager);
     }
 
     @Override

curator-framework/src/main/java/org/apache/curator/framework/imps/Watching.java

@@ -28,46 +28,36 @@ public class Watching {
     private final CuratorWatcher curatorWatcher;
     private final boolean watched;
     private final CuratorFrameworkImpl client;
-    private WatcherRemovalManager watcherRemovalManager;
     private NamespaceWatcher namespaceWatcher;
 
     public Watching(CuratorFrameworkImpl client, boolean watched) {
         this.client = client;
-        this.watcherRemovalManager = client.getWatcherRemovalManager();
         this.watcher = null;
         this.curatorWatcher = null;
         this.watched = watched;
     }
 
     public Watching(CuratorFrameworkImpl client, Watcher watcher) {
         this.client = client;
-        this.watcherRemovalManager = client.getWatcherRemovalManager();
         this.watcher = watcher;
         this.curatorWatcher = null;
         this.watched = false;
     }
 
     public Watching(CuratorFrameworkImpl client, CuratorWatcher watcher) {
         this.client = client;
-        this.watcherRemovalManager = client.getWatcherRemovalManager();
         this.watcher = null;
         this.curatorWatcher = watcher;
         this.watched = false;
     }
 
     public Watching(CuratorFrameworkImpl client) {
         this.client = client;
-        this.watcherRemovalManager = client.getWatcherRemovalManager();
         watcher = null;
         watched = false;
         curatorWatcher = null;
     }
 
-    Watching setWatcherRemovalManager(WatcherRemovalManager watcherRemovalManager) {
-        this.watcherRemovalManager = watcherRemovalManager;
-        return this;
-    }
-
     Watcher getWatcher(String unfixedPath) {
         namespaceWatcher = null;
         if (watcher != null) {
@@ -95,8 +85,8 @@ void commitWatcher(int rc, boolean isExists) {
             doCommit = (rc == KeeperException.Code.OK.intValue());
         }
 
-        if (doCommit && namespaceWatcher != null && watcherRemovalManager != null) {
-            watcherRemovalManager.add(namespaceWatcher);
+        if (doCommit && namespaceWatcher != null && client.getWatcherRemovalManager() != null) {
+            client.getWatcherRemovalManager().add(namespaceWatcher);
         }
     }
 }