From f3a5814bdc0d0e56ecb36c86b8e4ca160abbf063 Mon Sep 17 00:00:00 2001
From: stellamit <stellamit@440791e1-c2bf-4c1e-ad7c-caf3f8b0ebe8>
Date: Thu, 3 May 2012 20:09:39 +0000
Subject: [PATCH] NIHVIVO-3641 listener interface and methods for registering
 it for RDFService

---
 .../webapp/rdfservice/ChangeListener.java     | 39 +++++++++++++++++++
 .../vitro/webapp/rdfservice/RDFService.java   | 15 +++++++
 2 files changed, 54 insertions(+)
 create mode 100644 webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/ChangeListener.java

diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/ChangeListener.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/ChangeListener.java
new file mode 100644
index 000000000..874b45305
--- /dev/null
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/ChangeListener.java
@@ -0,0 +1,39 @@
+/* $This file is distributed under the terms of the license in /doc/license.txt$ */
+
+package edu.cornell.mannlib.vitro.webapp.rdfservice;
+
+/*
+ * 
+ * A listener that filters all its listening down to the single-statement level. Users of
+ * this class override addedStatement(statement) and removedStatement(statement).
+ *  
+ */
+
+public interface ChangeListener {
+		
+	/**
+	 * Override this to listen to all statements added to the RDF store. 
+	 * 
+	 * @param String serializedTriple - the added statement
+	 * @param RDFService.ModelSerializationFormat format - RDF format of serializedTriple
+	 * @param String graphURI - the graph to which the statement was added
+	 */
+	public void addedStatement(String serializedTriple, RDFService.ModelSerializationFormat format, String graphURI);
+	
+	/**
+	 * Override this to listen to all statements removed from the RDF store. 
+	 * 
+	 * @param String serializedTriple - the removed statement
+	 * @param RDFService.ModelSerializationFormat format - RDF format of serializedTriple
+	 * @param String graphURI - the graph from which the statement was removed
+	 */
+	public void removedStatement(String serializedTriple, RDFService.ModelSerializationFormat format, String graphURI);
+	
+	/**
+	 * Override this to listen to events pertaining to the given graphURI. 
+	 * 
+	 * @param String graphURI - the graph to which the event pertains
+	 * @param Object event - the event which occurred. 
+	 */
+	public void notifyEvent(String graphURI, Object event);
+}
diff --git a/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/RDFService.java b/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/RDFService.java
index 223ed1e29..76b947203 100644
--- a/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/RDFService.java
+++ b/webapp/src/edu/cornell/mannlib/vitro/webapp/rdfservice/RDFService.java
@@ -90,6 +90,21 @@ public interface RDFService {
 	 */
 	public String getDefaultReadGraphURI() throws RDFServiceException;
 	
+	/**
+	 * Register a listener to listen to changes in any graph in
+	 * the RDF store.
+	 * 
+	 * @return String URI of default read graph
+	 */
+	public void registerListener(ChangeListener changeListener) throws RDFServiceException;
+	
+	/**
+	 * Unregister a listener to listen to changes in any graph in
+	 * the RDF store.
+	 * 
+	 * @return String URI of default read graph
+	 */
+	public void unregisterListener(ChangeListener changeListener) throws RDFServiceException;
 
 	/**
 	 * Create a ChangeSet object