Save memory consumption by avoding unnecessary instantiation

Change-Id: I7ce66c11136653fabc490aa7f33fdadf4454d2cc
diff --git a/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/OpticalPathIntentCompiler.java b/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/OpticalPathIntentCompiler.java
index e6a20f7..2cf4ccb 100644
--- a/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/OpticalPathIntentCompiler.java
+++ b/core/net/src/main/java/org/onosproject/net/intent/impl/compiler/OpticalPathIntentCompiler.java
@@ -46,7 +46,7 @@
 import org.onosproject.net.resource.ResourceType;
 import org.onosproject.net.topology.TopologyService;
 
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
@@ -88,7 +88,8 @@
                                 Set<LinkResourceAllocations> resources) {
         LinkResourceAllocations allocations = assignWavelength(intent);
 
-        return Arrays.asList(new FlowRuleIntent(appId, createRules(intent, allocations), intent.resources()));
+        return Collections.singletonList(
+                new FlowRuleIntent(appId, createRules(intent, allocations), intent.resources()));
     }
 
     private LinkResourceAllocations assignWavelength(OpticalPathIntent intent) {