Lambda queries don't rely on driver state, and have separate package.
Lambda query returns unsorted set.

fix for ONOS-3620

Change-Id: Ifffd03271f9c8c02be8897c3891c80148342757e
diff --git a/core/api/src/main/java/org/onosproject/net/behaviour/LambdaQuery.java b/core/api/src/main/java/org/onosproject/net/behaviour/LambdaQuery.java
index e3b1d96..e18de74 100644
--- a/core/api/src/main/java/org/onosproject/net/behaviour/LambdaQuery.java
+++ b/core/api/src/main/java/org/onosproject/net/behaviour/LambdaQuery.java
@@ -21,7 +21,7 @@
 import org.onosproject.net.PortNumber;
 import org.onosproject.net.driver.HandlerBehaviour;
 
-import java.util.SortedSet;
+import java.util.Set;
 
 /**
  * A HandlerBehaviour to retrieve available wavelength resources.
@@ -29,12 +29,11 @@
 @Beta
 public interface LambdaQuery extends HandlerBehaviour {
 
-    // Currently returns set of FLEX GridType ochSignal instances
     /**
-     * Returns set of Lambda instances which can be used at the port.
+     * Returns set of OchSignal instances which can be used at the port.
      *
      * @param port to be checked for the available resources.
-     * @return Set of OchSignals which can be used at the port.
+     * @return set of OchSignals which can be used at the port.
      */
-    SortedSet<OchSignal> queryLambdas(PortNumber port);
+    Set<OchSignal> queryLambdas(PortNumber port);
 }
diff --git a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
index 6e944af..d1f6aab 100644
--- a/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
+++ b/core/net/src/main/java/org/onosproject/net/newresource/impl/ResourceDeviceListener.java
@@ -20,7 +20,6 @@
 import org.onlab.packet.MplsLabel;
 import org.onlab.packet.VlanId;
 import org.onlab.util.ItemNotFoundException;
-import org.onosproject.net.DefaultOchSignalComparator;
 import org.onosproject.net.Device;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.Port;
@@ -46,7 +45,6 @@
 import java.util.Collections;
 import java.util.List;
 import java.util.Set;
-import java.util.SortedSet;
 import java.util.concurrent.ExecutorService;
 import java.util.stream.Collectors;
 import java.util.stream.IntStream;
@@ -150,7 +148,7 @@
             }
 
             // for Lambdas
-            SortedSet<OchSignal> lambdas = queryLambdas(device.id(), port.number());
+            Set<OchSignal> lambdas = queryLambdas(device.id(), port.number());
             if (!lambdas.isEmpty()) {
                 adminService.registerResources(lambdas.stream()
                                                .map(portPath::child)
@@ -188,28 +186,28 @@
         executor.submit(() -> adminService.unregisterResources(resource));
     }
 
-    private SortedSet<OchSignal> queryLambdas(DeviceId did, PortNumber port) {
+    private Set<OchSignal> queryLambdas(DeviceId did, PortNumber port) {
         try {
             // DriverHandler does not provide a way to check if a
             // behaviour is supported.
             Driver driver = driverService.getDriver(did);
             if (driver == null || !driver.hasBehaviour(LambdaQuery.class)) {
-                return Collections.emptySortedSet();
+                return Collections.emptySet();
             }
             DriverHandler handler = driverService.createHandler(did);
             if (handler == null) {
-                return Collections.emptySortedSet();
+                return Collections.emptySet();
             }
             LambdaQuery query = handler.behaviour(LambdaQuery.class);
             if (query != null) {
                 return query.queryLambdas(port).stream()
                         .flatMap(x -> OchSignal.toFlexGrid(x).stream())
-                        .collect(Collectors.toCollection(DefaultOchSignalComparator::newOchSignalTreeSet));
+                        .collect(Collectors.toSet());
             } else {
-                return Collections.emptySortedSet();
+                return Collections.emptySet();
             }
         } catch (ItemNotFoundException e) {
-            return Collections.emptySortedSet();
+            return Collections.emptySet();
         }
     }