More progress.

git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@3861 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/as/com/threerings/presents/dobj/DObjectManager.as

@@ -0,0 +1,97 @@
+package com.threerings.presents.dobj {
+
+/**
+ * The distributed object manager is responsible for managing the creation
+ * and destruction of distributed objects and propagating dobj events to
+ * the appropriate subscribers. On the client, objects are managed as
+ * proxies to the real objects managed by the server, so attribute change
+ * requests are forwarded to the server and events coming down from the
+ * server are delivered to the local subscribers. On the server, the
+ * objects are managed directly.
+ */
+public interface DObjectManager
+{
+    /**
+     * Returns true if this distributed object manager is the
+     * authoritative manager for the specified distributed object, or fals
+     * if we are only providing a proxy to the object.
+     */
+    function isManager (obj :DObject) :Boolean;
+
+    /**
+     * Creates a distributed object instance of the supplied class and
+     * notifies the specified subscriber when it becomes available. This
+     * is the proper mechanism for constructing a new distributed object
+     * as it is the only way in which it can be properly registered with
+     * the dobj system.
+     *
+     * @param dclass The class object of the derived class of
+     * <code>DObject</code> (or <code>DObject.class</code> itself) that
+     * should be instantiated.
+     * @param target The subscriber to be notified when the object is
+     * created and available, or if there was a problem creating the
+     * object.
+     */
+    function createObject (dclass :Class, target :Subscriber) :void;
+
+    /**
+     * Requests that the specified subscriber be subscribed to the object
+     * identified by the supplied object id. That subscriber will be
+     * notified when the object is available or if the subscription
+     * request failed.
+     *
+     * @param oid The object id of the distributed object to which
+     * subscription is desired.
+     * @param target The subscriber to be subscribed.
+     *
+     * @see Subscriber#objectAvailable
+     * @see Subscriber#requestFailed
+     */
+    function subscribeToObject (oid :int, target :Subscriber) :void;
+
+    /**
+     * Requests that the specified subscriber be unsubscribed from the
+     * object identified by the supplied object id.
+     *
+     * @param oid The object id of the distributed object from which
+     * unsubscription is desired.
+     * @param target The subscriber to be unsubscribed.
+     */
+    function unsubscribeFromObject (oid :int, target :Subscriber) :void;
+
+    /**
+     * Requests that the specified object be destroyed. Once destroyed an
+     * object is removed from the runtime system and may no longer have
+     * events dispatched on it.
+     *
+     * @param oid The object id of the distributed object to be destroyed.
+     */
+    function destroyObject (oid :int) :void;
+
+    /**
+     * Posts a distributed object event into the system. Instead of
+     * requesting the modification of a distributed object attribute by
+     * calling the setter for that attribute on the object itself, an
+     * <code>AttributeChangedEvent</code> can be constructed and posted
+     * directly. This is true for all event types and is useful for
+     * situations where one doesn't have access to the object in question,
+     * but needs to affect some event.
+     *
+     * <p> This event will be forwarded to the ultimate manager of the
+     * object (on the client, this means it will be forwarded to the
+     * server) where it will be checked for validity and then applied to
+     * the object and dispatched to all its subscribers.
+     *
+     * @param event The event to be dispatched.
+     */
+    function postEvent (event :DEvent) :void;
+
+    /**
+     * When a distributed object removes its last subscriber, it will call
+     * this function to let the object manager know. The manager might
+     * then choose to flush this object from the system or unregister from
+     * some upstream manager whose object it was proxying, for example.
+     */
+    function removedLastSubscriber (obj :DObject, deathWish :Boolean) :void;
+}
+}