From 107c2bff032acf8833e6090f4281e80e539dfa5d Mon Sep 17 00:00:00 2001
From: Graham Triggs <gtriggs@duraspace.org>
Date: Wed, 11 Oct 2017 19:37:07 +0100
Subject: [PATCH] [VIVO-1399] Improve performance of Graph URI lookups

---
 .../rdfservice/impl/jena/RDFServiceJena.java  | 35 +++++++++++++------
 .../impl/jena/sdb/RDFServiceSDB.java          |  1 +
 .../impl/jena/tdb/RDFServiceTDB.java          |  2 ++
 .../impl/sparql/RDFServiceSparql.java         |  4 +--
 4 files changed, 29 insertions(+), 13 deletions(-)

diff --git a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/RDFServiceJena.java b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/RDFServiceJena.java
index 634269099..582c4f918 100644
--- a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/RDFServiceJena.java
+++ b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/RDFServiceJena.java
@@ -60,7 +60,10 @@ public abstract class RDFServiceJena extends RDFServiceImpl implements RDFServic
     private final static Log log = LogFactory.getLog(RDFServiceJena.class);
         
     protected abstract DatasetWrapper getDatasetWrapper();
-    
+
+    protected volatile boolean rebuildGraphURICache = true;
+    private final List<String> graphURIs = new ArrayList<>();
+
     @Override
 	public abstract boolean changeSetUpdate(ChangeSet changeSet) throws RDFServiceException;
      
@@ -527,18 +530,28 @@ public abstract class RDFServiceJena extends RDFServiceImpl implements RDFServic
 
     @Override
     public List<String> getGraphURIs() throws RDFServiceException {
-        DatasetWrapper dw = getDatasetWrapper();
-        try {
-            Dataset d = dw.getDataset();
-            List<String> graphURIs = new ArrayList<String>();
-            Iterator<String> nameIt = d.listNames();
-            while (nameIt.hasNext()) {
-                graphURIs.add(nameIt.next());
+        if (rebuildGraphURICache) {
+            synchronized (RDFServiceJena.class) {
+                if (rebuildGraphURICache) {
+                    rebuildGraphURICache = false;
+                    graphURIs.clear();
+
+                    DatasetWrapper dw = getDatasetWrapper();
+                    try {
+                        Dataset d = dw.getDataset();
+                        Iterator<String> nameIt = d.listNames();
+                        while (nameIt.hasNext()) {
+                            graphURIs.add(nameIt.next());
+                        }
+                        return graphURIs;
+                    } finally {
+                        dw.close();
+                    }
+                }
             }
-            return graphURIs;
-        } finally {
-            dw.close();
         }
+
+        return graphURIs;
     }
 
     @Override
diff --git a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/sdb/RDFServiceSDB.java b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/sdb/RDFServiceSDB.java
index 426c1ae34..3da53123d 100644
--- a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/sdb/RDFServiceSDB.java
+++ b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/sdb/RDFServiceSDB.java
@@ -110,6 +110,7 @@ public class RDFServiceSDB extends RDFServiceJena implements RDFService {
             abortTransaction(sdbConn);
             throw new RDFServiceException(e);
         } finally {
+            rebuildGraphURICache = true;
             close(sdbConn);
         }
     }
diff --git a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/tdb/RDFServiceTDB.java b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/tdb/RDFServiceTDB.java
index 89843a11f..5533574e4 100644
--- a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/tdb/RDFServiceTDB.java
+++ b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/jena/tdb/RDFServiceTDB.java
@@ -88,6 +88,8 @@ public class RDFServiceTDB extends RDFServiceJena {
 		} catch (Exception e) {
 			log.error(e, e);
 			throw new RDFServiceException(e);
+		} finally {
+			rebuildGraphURICache = true;
 		}
 	}
 
diff --git a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/sparql/RDFServiceSparql.java b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/sparql/RDFServiceSparql.java
index a94144f2b..1451be017 100644
--- a/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/sparql/RDFServiceSparql.java
+++ b/api/src/main/java/edu/cornell/mannlib/vitro/webapp/rdfservice/impl/sparql/RDFServiceSparql.java
@@ -514,7 +514,7 @@ public class RDFServiceSparql extends RDFServiceImpl implements RDFService {
 		}
 	}
 
-	public void addModel(Model model, String graphURI) throws RDFServiceException {
+	private void addModel(Model model, String graphURI) throws RDFServiceException {
 		try {
 		    long start = System.currentTimeMillis();
 			verbModel(model, graphURI, "INSERT");
@@ -524,7 +524,7 @@ public class RDFServiceSparql extends RDFServiceImpl implements RDFService {
 		}
 	}
 
-	public void deleteModel(Model model, String graphURI) throws RDFServiceException {
+	private void deleteModel(Model model, String graphURI) throws RDFServiceException {
 		try {
 			verbModel(model, graphURI, "DELETE");
 		} finally {