Move laziness down to avoid initialising MessageBusDocumentAccess unless _used_

1 files changed, 88 insertions, 21 deletions

diff --git a/container-core/src/main/java/com/yahoo/container/core/documentapi/MessageBusDocumentAccessProvider.java b/container-core/src/main/java/com/yahoo/container/core/documentapi/MessageBusDocumentAccessProvider.java
index cd6a2fc8b12..78653a81e58 100644
--- a/container-core/src/main/java/com/yahoo/container/core/documentapi/MessageBusDocumentAccessProvider.java
+++ b/container-core/src/main/java/com/yahoo/container/core/documentapi/MessageBusDocumentAccessProvider.java
@@ -4,51 +4,118 @@ import com.google.inject.Inject;
 import com.yahoo.component.AbstractComponent;
 import com.yahoo.container.di.componentgraph.Provider;
 import com.yahoo.document.config.DocumentmanagerConfig;
+import com.yahoo.document.select.parser.ParseException;
+import com.yahoo.documentapi.AsyncParameters;
+import com.yahoo.documentapi.AsyncSession;
 import com.yahoo.documentapi.DocumentAccess;
+import com.yahoo.documentapi.DocumentAccessParams;
+import com.yahoo.documentapi.SubscriptionParameters;
+import com.yahoo.documentapi.SubscriptionSession;
+import com.yahoo.documentapi.SyncParameters;
+import com.yahoo.documentapi.SyncSession;
+import com.yahoo.documentapi.VisitorDestinationParameters;
+import com.yahoo.documentapi.VisitorDestinationSession;
+import com.yahoo.documentapi.VisitorParameters;
+import com.yahoo.documentapi.VisitorSession;
 import com.yahoo.documentapi.messagebus.MessageBusDocumentAccess;
 import com.yahoo.documentapi.messagebus.MessageBusParams;
 import com.yahoo.documentapi.messagebus.loadtypes.LoadTypeSet;
 import com.yahoo.vespa.config.content.LoadTypeConfig;
 
 /**
- * Has a lazily populated reference to a {@link MessageBusDocumentAccess}.
+ * Lets a lazily initialised DocumentAccess forwarding to a real MessageBusDocumentAccess be injected in containers.
  *
  * @author jonmv
  */
 public class MessageBusDocumentAccessProvider extends AbstractComponent implements Provider<DocumentAccess> {
 
-    private final DocumentmanagerConfig documentmanagerConfig;
-    private final LoadTypeConfig loadTypeConfig;
-    private final Object monitor = new Object();
-    private boolean shutDown = false;
-    private DocumentAccess access = null;
+    private final DocumentAccess access;
 
     @Inject
+    // TODO jonmv: Have Slobrok and RPC config injected as well.
     public MessageBusDocumentAccessProvider(DocumentmanagerConfig documentmanagerConfig, LoadTypeConfig loadTypeConfig) {
-        this.documentmanagerConfig = documentmanagerConfig;
-        this.loadTypeConfig = loadTypeConfig;
+        this.access = new LazyForwardingMessageBusDocumentAccess(documentmanagerConfig, loadTypeConfig);
     }
 
     @Override
     public DocumentAccess get() {
-        synchronized (monitor) {
-            if (access == null) {
-                if (shutDown)
-                    throw new IllegalStateException("This document access has been shut down");
-
-                access = new MessageBusDocumentAccess((MessageBusParams) new MessageBusParams(new LoadTypeSet(loadTypeConfig)).setDocumentmanagerConfig(documentmanagerConfig));
-            }
-            return access;
-        }
+        return access;
     }
 
     @Override
     public void deconstruct() {
-        synchronized (monitor) {
-            shutDown = true;
-            if (access != null)
-                access.shutdown();
+        access.shutdown();
+    }
+
+
+    private static class LazyForwardingMessageBusDocumentAccess extends DocumentAccess {
+
+        private final DocumentmanagerConfig documentmanagerConfig;
+        private final LoadTypeConfig loadTypeConfig;
+        private final Object monitor = new Object();
+
+        private DocumentAccess delegate = null;
+        private boolean shutDown = false;
+
+        public LazyForwardingMessageBusDocumentAccess(DocumentmanagerConfig documentmanagerConfig,
+                                                      LoadTypeConfig loadTypeConfig) {
+            super(new DocumentAccessParams().setDocumentmanagerConfig(documentmanagerConfig));
+            this.documentmanagerConfig = documentmanagerConfig;
+            this.loadTypeConfig = loadTypeConfig;
         }
+
+        private DocumentAccess delegate() {
+            synchronized (monitor) {
+                if (delegate == null) {
+                    if (shutDown)
+                        throw new IllegalStateException("This document access has been shut down");
+
+                    delegate = new MessageBusDocumentAccess((MessageBusParams) new MessageBusParams(new LoadTypeSet(loadTypeConfig)).setDocumentmanagerConfig(documentmanagerConfig));
+                }
+                return delegate;
+            }
+        }
+
+        @Override
+        public void shutdown() {
+            synchronized (monitor) {
+                super.shutdown();
+                shutDown = true;
+                if (delegate != null)
+                    delegate.shutdown();
+            }
+        }
+
+        @Override
+        public SyncSession createSyncSession(SyncParameters parameters) {
+            return delegate().createSyncSession(parameters);
+        }
+
+        @Override
+        public AsyncSession createAsyncSession(AsyncParameters parameters) {
+            return delegate().createAsyncSession(parameters);
+        }
+
+        @Override
+        public VisitorSession createVisitorSession(VisitorParameters parameters) throws ParseException {
+            return delegate().createVisitorSession(parameters);
+        }
+
+        @Override
+        public VisitorDestinationSession createVisitorDestinationSession(VisitorDestinationParameters parameters) {
+            return delegate().createVisitorDestinationSession(parameters);
+        }
+
+        @Override
+        public SubscriptionSession createSubscription(SubscriptionParameters parameters) {
+            return delegate().createSubscription(parameters);
+        }
+
+        @Override
+        public SubscriptionSession openSubscription(SubscriptionParameters parameters) {
+            return delegate().openSubscription(parameters);
+        }
+
     }
 
 }