Implement basic unit tests for RouteHandler

In addition,
    - Refactor Segment Routing unit test mocking

Change-Id: I94cb75a8b12944264faa76301d58ee19f246d584
diff --git a/src/test/java/org/onosproject/segmentrouting/MockFlowObjectiveService.java b/src/test/java/org/onosproject/segmentrouting/MockFlowObjectiveService.java
new file mode 100644
index 0000000..138b98a
--- /dev/null
+++ b/src/test/java/org/onosproject/segmentrouting/MockFlowObjectiveService.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2017-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting;
+
+import org.onlab.packet.MacAddress;
+import org.onlab.packet.VlanId;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flow.criteria.Criterion;
+import org.onosproject.net.flow.criteria.EthCriterion;
+import org.onosproject.net.flow.criteria.VlanIdCriterion;
+import org.onosproject.net.flow.instructions.Instruction;
+import org.onosproject.net.flow.instructions.Instructions;
+import org.onosproject.net.flow.instructions.L2ModificationInstruction;
+import org.onosproject.net.flowobjective.FlowObjectiveServiceAdapter;
+import org.onosproject.net.flowobjective.ForwardingObjective;
+import org.onosproject.net.flowobjective.Objective;
+
+import java.util.Map;
+
+/**
+ * Mock Flow Objective Service.
+ */
+public class MockFlowObjectiveService extends FlowObjectiveServiceAdapter {
+    private Map<MockBridgingTableKey, MockBridgingTableValue> bridgingTable;
+    private Map<Integer, TrafficTreatment> nextTable;
+
+    MockFlowObjectiveService(Map<MockBridgingTableKey, MockBridgingTableValue> bridgingTable,
+                             Map<Integer, TrafficTreatment> nextTable) {
+        this.bridgingTable = bridgingTable;
+        this.nextTable = nextTable;
+    }
+
+    @Override
+    public void forward(DeviceId deviceId, ForwardingObjective forwardingObjective) {
+        TrafficSelector selector = forwardingObjective.selector();
+        TrafficTreatment treatment = nextTable.get(forwardingObjective.nextId());
+        MacAddress macAddress = ((EthCriterion) selector.getCriterion(Criterion.Type.ETH_DST)).mac();
+        VlanId vlanId = ((VlanIdCriterion) selector.getCriterion(Criterion.Type.VLAN_VID)).vlanId();
+
+        boolean popVlan = treatment.allInstructions().stream()
+                .filter(instruction -> instruction.type().equals(Instruction.Type.L2MODIFICATION))
+                .anyMatch(instruction -> ((L2ModificationInstruction) instruction).subtype()
+                        .equals(L2ModificationInstruction.L2SubType.VLAN_POP));
+        PortNumber portNumber = treatment.allInstructions().stream()
+                .filter(instruction -> instruction.type().equals(Instruction.Type.OUTPUT))
+                .map(instruction -> ((Instructions.OutputInstruction) instruction).port()).findFirst().orElse(null);
+        if (portNumber == null) {
+            throw new IllegalArgumentException();
+        }
+
+        Objective.Operation op = forwardingObjective.op();
+
+        MockBridgingTableKey btKey = new MockBridgingTableKey(deviceId, macAddress, vlanId);
+        MockBridgingTableValue btValue = new MockBridgingTableValue(popVlan, portNumber);
+
+        if (op.equals(Objective.Operation.ADD)) {
+            bridgingTable.put(btKey, btValue);
+        } else if (op.equals(Objective.Operation.REMOVE)) {
+            bridgingTable.remove(btKey, btValue);
+        } else {
+            throw new IllegalArgumentException();
+        }
+    }
+}