svn commit: r1367190 - /jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java

[an...@apache.org]

Author: andy
Date: Mon Jul 30 17:42:07 2012
New Revision: 1367190

URL: http://svn.apache.org/viewvc?rev=1367190&view=rev
Log:
JENA-288

Fix for known not-to-exist graph and a constrained variable.

Modified:
    jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java

Modified: jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java
URL: http://svn.apache.org/viewvc/jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java?rev=1367190&r1=1367189&r2=1367190&view=diff
==============================================================================
--- jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java (original)
+++ jena/trunk/jena-arq/src/main/java/com/hp/hpl/jena/sparql/engine/main/iterator/QueryIterGraph.java Mon Jul 30 17:42:07 2012
@@ -153,6 +153,10 @@ public class QueryIterGraph extends Quer
             Node gn = graphNames.next() ;
 
             QueryIterator qIter = buildIterator(parentBinding, gn, opGraph, getExecContext()) ;
+            if ( qIter == null )
+                // Know to be nothing (e.g. graph does not exist). 
+                return null ;
+            
             if ( Var.isVar(opGraph.getNode()) )
             {
                 // This is the join of the graph node variable to the sub-pattern solution.
@@ -165,7 +169,7 @@ public class QueryIterGraph extends Quer
             return qIter ;
         }
         
-
+        // Create the iterator - or return null if there can't be any results.
         protected static QueryIterator buildIterator(Binding binding, Node graphNode, OpGraph opGraph, ExecutionContext outerCxt)
         {
             if ( !graphNode.isURI() )