MONDRIAN: Fixes an issue with the test suite and the SegmentCache pro…

…perty. Setting it to null at runtime wouldn't disable the cache if one was previously configured.

[git-p4: depot-paths = "//open/mondrian/": change = 14707]

src/main/mondrian/rolap/agg/SegmentCacheWorker.java

@@ -38,11 +38,13 @@ public final class SegmentCacheWorker {
 
     // Always call prior to using segmentCache
     private synchronized static void initCache() {
+        boolean segmentCacheFound = false;
         // First try to get the segmentcache impl class from
         // mondrian properties.
         final String cacheName =
             MondrianProperties.instance().SegmentCache.get();
         if (cacheName != null) {
+            segmentCacheFound = true;
             setCache(cacheName);
         }
 
@@ -55,9 +57,15 @@ private synchronized static void initCache() {
                 serviceDiscovery.getImplementor();
             if (implementors.size() > 0) {
                 // The contract is to use the first implementation found.
+                segmentCacheFound = true;
                 setCache(implementors.get(0).getName());
             }
         }
+
+        if (!segmentCacheFound) {
+            // No cache were found. Let's disable it.
+            setCache(null);
+        }
     }
 
     /**