Performance improvement when handling host move events

- Avoid querying shouldProgram every time
- Override flows directly instead of remove and add
- Remove unnecessary event handling delay since we have in-order execution now
- Avoid re-initiation of shouldProgram
- Make sure executors are shut down during SR deactivation

Change-Id: I28e383ed2dcb66d503da25934456008e83683b78
diff --git a/apps/segmentrouting/app/src/test/java/org/onosproject/segmentrouting/DefaultRoutingHandlerTest.java b/apps/segmentrouting/app/src/test/java/org/onosproject/segmentrouting/DefaultRoutingHandlerTest.java
index 05abcfc..28847c6 100644
--- a/apps/segmentrouting/app/src/test/java/org/onosproject/segmentrouting/DefaultRoutingHandlerTest.java
+++ b/apps/segmentrouting/app/src/test/java/org/onosproject/segmentrouting/DefaultRoutingHandlerTest.java
@@ -66,6 +66,12 @@
         dfh = new DefaultRoutingHandler(srManager);
     }
 
+    private void clearCache() {
+        dfh.invalidateShouldProgramCache(DEV1A);
+        dfh.invalidateShouldProgramCache(DEV1B);
+        dfh.invalidateShouldProgramCache(DEV2);
+    }
+
     // Node 1 is the master of switch 1A, 1B, and 2
     @Test
     public void testShouldHandleRoutingCase1() {
@@ -87,6 +93,7 @@
         assertTrue(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -96,6 +103,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 3 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE3, IP3)).anyTimes();
@@ -127,6 +135,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program 2
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -136,6 +145,7 @@
         assertTrue(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 3 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE3, IP3)).anyTimes();
@@ -168,6 +178,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -177,6 +188,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 3 should program 2
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE3, IP3)).anyTimes();
@@ -208,6 +220,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -217,6 +230,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 3 should program 1A, 1B and 2
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE3, IP3)).anyTimes();
@@ -233,6 +247,7 @@
         replay(srManager.mastershipService);
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 1 should program 1A, 1B
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE1, IP1)).anyTimes();
@@ -242,6 +257,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -251,6 +267,7 @@
         assertFalse(dfh.shouldProgram(DEV2));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 3 should program 2
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE3, IP3)).anyTimes();
@@ -279,6 +296,7 @@
         assertTrue(dfh.shouldProgram(DEV1B));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -293,6 +311,7 @@
         replay(srManager.mastershipService);
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 1 should program 1A, 1B
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE1, IP1)).anyTimes();
@@ -301,6 +320,7 @@
         assertTrue(dfh.shouldProgram(DEV1B));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();
@@ -327,6 +347,7 @@
         assertFalse(dfh.shouldProgram(DEV1B));
 
         reset(srManager.clusterService);
+        clearCache();
 
         // Node 2 should program no device
         expect(srManager.clusterService.getLocalNode()).andReturn(new DefaultControllerNode(NODE2, IP2)).anyTimes();