Added getCriterion method to TrafficSelector

Change-Id: I72d89d878e1fae95d1e16d9ed473b7711895e478

@@ -55,6 +55,16 @@ public final class DefaultTrafficSelector implements TrafficSelector {
     }
 
     @Override
+    public Criterion getCriterion(Criterion.Type type) {
+        for (Criterion c : criteria) {
+            if (c.type() == type) {
+                return c;
+            }
+        }
+        return null;
+    }
+
+    @Override
     public int hashCode() {
         return Objects.hash(criteria);
     }

@@ -39,6 +39,15 @@ public interface TrafficSelector {
     Set<Criterion> criteria();
 
     /**
+     * Returns the selection criterion for a particular type, if it exists in
+     * this traffic selector.
+     *
+     * @param type criterion type to look up
+     * @return the criterion of the specified type if one exists, otherwise null
+     */
+    Criterion getCriterion(Criterion.Type type);
+
+    /**
      * Builder of traffic selector entities.
      */
     public interface Builder {

@@ -6,12 +6,11 @@ import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
 import static org.onlab.onos.net.flow.FlowRuleEvent.Type.RULE_ADDED;
+import static org.onlab.onos.net.flow.FlowRuleEvent.Type.RULE_ADD_REQUESTED;
 import static org.onlab.onos.net.flow.FlowRuleEvent.Type.RULE_REMOVED;
+import static org.onlab.onos.net.flow.FlowRuleEvent.Type.RULE_REMOVE_REQUESTED;
 import static org.onlab.onos.net.flow.FlowRuleEvent.Type.RULE_UPDATED;
 
-
-import static org.onlab.onos.net.flow.FlowRuleEvent.Type.*;
-
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -39,6 +38,7 @@ import org.onlab.onos.net.Port;
 import org.onlab.onos.net.PortNumber;
 import org.onlab.onos.net.device.DeviceListener;
 import org.onlab.onos.net.device.DeviceService;
+import org.onlab.onos.net.flow.BatchOperation;
 import org.onlab.onos.net.flow.CompletedBatchOperation;
 import org.onlab.onos.net.flow.DefaultFlowEntry;
 import org.onlab.onos.net.flow.DefaultFlowRule;
@@ -58,7 +58,6 @@ import org.onlab.onos.net.flow.TrafficSelector;
 import org.onlab.onos.net.flow.TrafficTreatment;
 import org.onlab.onos.net.flow.criteria.Criterion;
 import org.onlab.onos.net.flow.instructions.Instruction;
-import org.onlab.onos.net.flow.BatchOperation;
 import org.onlab.onos.net.provider.AbstractProvider;
 import org.onlab.onos.net.provider.ProviderId;
 import org.onlab.onos.store.trivial.impl.SimpleFlowRuleStore;
@@ -583,6 +582,12 @@ public class FlowRuleManagerTest {
         }
 
         @Override
+        public Criterion getCriterion(
+                org.onlab.onos.net.flow.criteria.Criterion.Type type) {
+            return null;
+        }
+
+        @Override
         public int hashCode() {
             return testval;
         }
@@ -594,6 +599,7 @@ public class FlowRuleManagerTest {
             }
             return false;
         }
+
     }
 
     private class TestTreatment implements TrafficTreatment {

 package org.onlab.onos.net.intent;
 
+import static org.onlab.onos.net.NetTestTools.createPath;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -12,12 +14,11 @@ import org.onlab.onos.net.Path;
 import org.onlab.onos.net.flow.TrafficSelector;
 import org.onlab.onos.net.flow.TrafficTreatment;
 import org.onlab.onos.net.flow.criteria.Criterion;
+import org.onlab.onos.net.flow.criteria.Criterion.Type;
 import org.onlab.onos.net.flow.instructions.Instruction;
 import org.onlab.onos.net.topology.LinkWeight;
 import org.onlab.onos.net.topology.PathService;
 
-import static org.onlab.onos.net.NetTestTools.createPath;
-
 /**
  * Common mocks used by the intent framework tests.
  */
@@ -30,6 +31,11 @@ public class IntentTestsMocks {
         public Set<Criterion> criteria() {
             return new HashSet<>();
         }
+
+        @Override
+        public Criterion getCriterion(Type type) {
+            return null;
+        }
     }
 
     /**