- Added handling null migrationMap

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/power/PowerDatacenter.java

@@ -147,25 +147,27 @@ public class PowerDatacenter extends Datacenter {
 			if (!isDisableMigrations()) {
 				List<Map<String, Object>> migrationMap = getVmAllocationPolicy().optimizeAllocation(getVmList());
 
-				for (Map<String, Object> migrate : migrationMap) {
-					Vm vm = (Vm) migrate.get("vm");
-					PowerHost targetHost = (PowerHost) migrate.get("host");
-					PowerHost oldHost = (PowerHost) vm.getHost();
-
-					targetHost.addMigratingInVm(vm);
-
-					if (oldHost == null) {
-						Log.formatLine("%.2f: Migration of VM #%d to Host #%d is started", CloudSim.clock(), vm.getId(), targetHost.getId());
-					} else {
-						Log.formatLine("%.2f: Migration of VM #%d from Host #%d to Host #%d is started", CloudSim.clock(), vm.getId(), oldHost.getId(), targetHost.getId());
+				if (migrationMap != null) {
+					for (Map<String, Object> migrate : migrationMap) {
+						Vm vm = (Vm) migrate.get("vm");
+						PowerHost targetHost = (PowerHost) migrate.get("host");
+						PowerHost oldHost = (PowerHost) vm.getHost();
+	
+						targetHost.addMigratingInVm(vm);
+	
+						if (oldHost == null) {
+							Log.formatLine("%.2f: Migration of VM #%d to Host #%d is started", CloudSim.clock(), vm.getId(), targetHost.getId());
+						} else {
+							Log.formatLine("%.2f: Migration of VM #%d from Host #%d to Host #%d is started", CloudSim.clock(), vm.getId(), oldHost.getId(), targetHost.getId());
+						}
+	
+						incrementMigrationCount();
+	
+						vm.setInMigration(true);
+	
+						/** VM migration delay = RAM / bandwidth + C    (C = 10 sec) **/
+						send(getId(), vm.getRam() / ((double) vm.getBw() / 8000) + 0, CloudSimTags.VM_MIGRATE, migrate);
 					}
-
-					incrementMigrationCount();
-
-					vm.setInMigration(true);
-
-					/** VM migration delay = RAM / bandwidth + C    (C = 10 sec) **/
-					send(getId(), vm.getRam() / ((double) vm.getBw() / 8000) + 0, CloudSimTags.VM_MIGRATE, migrate);
 				}
 			}
 

modules/cloudsim/src/main/java/org/cloudbus/cloudsim/power/PowerDatacenterNonPowerAware.java

@@ -121,25 +121,27 @@ public class PowerDatacenterNonPowerAware extends PowerDatacenter {
 			if (!isDisableMigrations()) {
 				List<Map<String, Object>> migrationMap = getVmAllocationPolicy().optimizeAllocation(getVmList());
 
-				for (Map<String, Object> migrate : migrationMap) {
-					Vm vm = (Vm) migrate.get("vm");
-					PowerHost targetHost = (PowerHost) migrate.get("host");
-					PowerHost oldHost = (PowerHost) vm.getHost();
-
-					targetHost.addMigratingInVm(vm);
-
-					if (oldHost == null) {
-						Log.formatLine("%.2f: Migration of VM #%d to Host #%d is started", CloudSim.clock(), vm.getId(), targetHost.getId());
-					} else {
-						Log.formatLine("%.2f: Migration of VM #%d from Host #%d to Host #%d is started", CloudSim.clock(), vm.getId(), oldHost.getId(), targetHost.getId());
+				if (migrationMap != null) {
+					for (Map<String, Object> migrate : migrationMap) {
+						Vm vm = (Vm) migrate.get("vm");
+						PowerHost targetHost = (PowerHost) migrate.get("host");
+						PowerHost oldHost = (PowerHost) vm.getHost();
+	
+						targetHost.addMigratingInVm(vm);
+	
+						if (oldHost == null) {
+							Log.formatLine("%.2f: Migration of VM #%d to Host #%d is started", CloudSim.clock(), vm.getId(), targetHost.getId());
+						} else {
+							Log.formatLine("%.2f: Migration of VM #%d from Host #%d to Host #%d is started", CloudSim.clock(), vm.getId(), oldHost.getId(), targetHost.getId());
+						}
+	
+						incrementMigrationCount();
+	
+						vm.setInMigration(true);
+	
+						/** VM migration delay = RAM / bandwidth + C    (C = 10 sec) **/
+						send(getId(), vm.getRam() / ((double) vm.getBw() / 8000) + 10, CloudSimTags.VM_MIGRATE, migrate);
 					}
-
-					incrementMigrationCount();
-
-					vm.setInMigration(true);
-
-					/** VM migration delay = RAM / bandwidth + C    (C = 10 sec) **/
-					send(getId(), vm.getRam() / ((double) vm.getBw() / 8000) + 10, CloudSimTags.VM_MIGRATE, migrate);
 				}
 			}