1 files changed, 94 insertions, 0 deletions
diff --git a/rdf/base/nsIRDFObserver.idl b/rdf/base/nsIRDFObserver.idl
new file mode 100644
index 0000000000..1923c5b38e
--- /dev/null
+++ b/rdf/base/nsIRDFObserver.idl
@@ -0,0 +1,94 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+#include "nsIRDFResource.idl"
+#include "nsIRDFNode.idl"
+
+interface nsIRDFDataSource;
+
+// An nsIRDFObserver object is an observer that will be notified
+// when assertions are made or removed from a datasource
+[scriptable, uuid(3CC75360-484A-11D2-BC16-00805F912FE7)]
+interface nsIRDFObserver : nsISupports {
+    /**
+     * This method is called whenever a new assertion is made
+     * in the data source
+     * @param aDataSource the datasource that is issuing
+     *   the notification.
+     * @param aSource the subject of the assertion
+     * @param aProperty the predicate of the assertion
+     * @param aTarget the object of the assertion
+     */
+    void onAssert(in nsIRDFDataSource aDataSource,
+                  in nsIRDFResource aSource,
+                  in nsIRDFResource aProperty,
+                  in nsIRDFNode     aTarget);
+
+    /**
+     * This method is called whenever an assertion is removed
+     * from the data source
+     * @param aDataSource the datasource that is issuing
+     *   the notification.
+     * @param aSource the subject of the assertion
+     * @param aProperty the predicate of the assertion
+     * @param aTarget the object of the assertion
+     */
+    void onUnassert(in nsIRDFDataSource aDataSource,
+                    in nsIRDFResource aSource,
+                    in nsIRDFResource aProperty,
+                    in nsIRDFNode     aTarget);
+
+    /**
+     * This method is called when the object of an assertion
+     * changes from one value to another.
+     * @param aDataSource the datasource that is issuing
+     *   the notification.
+     * @param aSource the subject of the assertion
+     * @param aProperty the predicate of the assertion
+     * @param aOldTarget the old object of the assertion
+     * @param aNewTarget the new object of the assertion
+     */
+    void onChange(in nsIRDFDataSource aDataSource,
+                  in nsIRDFResource aSource,
+                  in nsIRDFResource aProperty,
+                  in nsIRDFNode     aOldTarget,
+                  in nsIRDFNode     aNewTarget);
+
+    /**
+     * This method is called when the subject of an assertion
+     * changes from one value to another.
+     * @param aDataSource the datasource that is issuing
+     *   the notification.
+     * @param aOldSource the old subject of the assertion
+     * @param aNewSource the new subject of the assertion
+     * @param aProperty the predicate of the assertion
+     * @param aTarget the object of the assertion
+     */
+    void onMove(in nsIRDFDataSource aDataSource,
+                in nsIRDFResource aOldSource,
+                in nsIRDFResource aNewSource,
+                in nsIRDFResource aProperty,
+                in nsIRDFNode     aTarget);
+
+    /**
+     * This method is called when a datasource is about to
+     * send several notifications at once. The observer can
+     * use this as a cue to optimize its behavior. The observer
+     * can expect the datasource to call endUpdateBatch() when
+     * the group of notifications has completed.
+     * @param aDataSource the datasource that is going to
+     *   be issuing the notifications.
+     */
+    void onBeginUpdateBatch(in nsIRDFDataSource aDataSource);
+
+    /**
+     * This method is called when a datasource has completed
+     * issuing a notification group.
+     * @param aDataSource the datasource that has finished
+     *   issuing a group of notifications
+     */
+    void onEndUpdateBatch(in nsIRDFDataSource aDataSource);
+};