Merges PowerSupply to PowerModel classes

- The PowerSupply was just delegating multiple methods to PowerModel.
  PowerSupply was merged into PowerModel and the former removed.
  After this, the way to use PowerModel is as before the release 2.0.0,
  with all benefits of incorporating power-awareness into regular
  classes, namely DatacenterSimple, HostSimple and VmSimple.
- Stores the active state of Hosts in the StateHistory by using
  the Host's active attribute, instead of checking the utilization of CPU.
- Updates Datacenter documentation to show that the computed
  power usage is and estimation. It also shows how to compute actual
  power usage if Host's StateHistory is enabled.

Signed-off-by: Manoel Campos <manoelcampos@gmail.com>

cloudsim-plus-benchmarks/pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>org.cloudsimplus</groupId>
     <artifactId>cloudsim-plus-benchmarks</artifactId>
-    <version>2.1.0</version>
+    <version>2.2.0</version>
     <name>CloudSim Plus Benchmarks</name>
     <description>A module containing benchmarks created using JMH (Java Microbenchmark Harness framework) to assess CloudSim Plus performance</description>
     <url>http://cloudsimplus.org</url>

cloudsim-plus-examples/pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>org.cloudsimplus</groupId>
     <artifactId>cloudsim-plus-examples</artifactId>
-    <version>2.1.0</version>
+    <version>2.2.0</version>
     <name>CloudSim Plus Examples</name>
     <description>
         Ready-to-run examples of how to use CloudSim Plus API.

cloudsim-plus-examples/src/main/java/org/cloudsimplus/examples/PowerExample.java

@@ -55,7 +55,7 @@
 /**
  * A example showing how to show Hosts power consumption.
  * Realize that for this goal, you define a {@link PowerModel}
- * for each Host by calling {@code host.getPowerSupply().setPowerModel(powerModel)}.
+ * for each Host by calling {@code host.setPowerModel(powerModel)}.
  *
  * <p>It creates the number of cloudlets defined in
  * {@link #CLOUDLETS}. All cloudlets will required 100% of PEs they are using all the time.
@@ -168,7 +168,7 @@ private void printHostCpuUtilizationAndPowerConsumption() {
                  * This way, to get the total power consumed for each 10 seconds interval,
                  * the power consumption is multipled by the time interval.
                 */
-                final double wattsPerInterval = host.getPowerSupply().getPowerModel().getPower(utilizationPercent)*SCHEDULING_INTERVAL;
+                final double wattsPerInterval = host.getPowerModel().getPower(utilizationPercent)*SCHEDULING_INTERVAL;
                 totalPower += wattsPerInterval;
                 System.out.printf("\tTime %6.0f | CPU Utilization %6.2f%% | Power Consumption: %8.2f Watts in %d Seconds\n",
                     time, utilizationPercent*100, wattsPerInterval, SCHEDULING_INTERVAL);
@@ -212,7 +212,7 @@ private Host createPowerHost() {
         final VmScheduler vmScheduler = new VmSchedulerTimeShared();
 
         final Host host = new HostSimple(ram, bw, storage, peList);
-        host.getPowerSupply().setPowerModel(powerModel);
+        host.setPowerModel(powerModel);
         host
             .setRamProvisioner(ramProvisioner)
             .setBwProvisioner(bwProvisioner)

cloudsim-plus-examples/src/main/java/org/cloudsimplus/examples/migration/MigrationExample2_PowerUsage.java

@@ -87,7 +87,7 @@
  *
  * <p>This VmAllocationPolicy considers the power usage of Hosts to place VMs.
  * So that, a {@link org.cloudbus.cloudsim.power.models.PowerModel} is being
- * set to every created Host by means of {@code host.getPowerSupply().setPowerModel(powerModel)}.</p>
+ * set to every created Host by means of {@code host.setPowerModel(powerModel)}.</p>
  *
  * <p>The example uses a {@link UtilizationModelDynamic} that defines the CPU usage of cloudlets
  *  increases along the simulation time.</p>
@@ -261,7 +261,7 @@ private void printHostCpuUsageAndPowerConsumption(final Host host) {
         int time = 0;
         for (int i = 0; i < utilizationHistory.length; i++) {
             final double cpuUsage = utilizationHistory[i];
-            System.out.printf("Time: %6d | %9.2f | %.2f\n", i*SCHEDULE_INTERVAL, cpuUsage, host.getPowerSupply().getPower(cpuUsage));
+            System.out.printf("Time: %6d | %9.2f | %.2f\n", i*SCHEDULE_INTERVAL, cpuUsage, host.getPowerModel().getPower(cpuUsage));
             time += SCHEDULE_INTERVAL;
         }
         System.out.println();
@@ -437,7 +437,7 @@ public Host createHost(int numberOfPes, long mipsByPe) {
                 .setBwProvisioner(new ResourceProvisionerSimple())
                 .setVmScheduler(new VmSchedulerTimeShared());
             host.enableStateHistory();
-            host.getPowerSupply().setPowerModel(new PowerModelLinear(800, 0.3));
+            host.setPowerModel(new PowerModelLinear(800, 0.3));
             return host;
     }
 

cloudsim-plus-testbeds/pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>org.cloudsimplus</groupId>
     <artifactId>cloudsim-plus-testbeds</artifactId>
-    <version>2.1.0</version>
+    <version>2.2.0</version>
     <name>CloudSim Plus Testbeds</name>
     <description>
         A set of more complex and comprehensive CloudSim Plus testbeds used to assess

cloudsim-plus-testbeds/src/main/java/org/cloudsimplus/migration/VmMigrationWhenCpuMetricIsViolatedExample.java

@@ -291,7 +291,7 @@ private Datacenter createDatacenter() {
     public static Host createHost(int id, int numberOfPes, long mipsByPe) {
         List<Pe> peList = createPeList(numberOfPes, mipsByPe);
         Host host = new HostSimple(HOST_RAM, HOST_BW, HOST_STORAGE, peList);
-        host.getPowerSupply().setPowerModel(new PowerModelLinear(1000, 0.7))
+        host.setPowerModel(new PowerModelLinear(1000, 0.7))
                 .setRamProvisioner(new ResourceProvisionerSimple())
                 .setBwProvisioner(new ResourceProvisionerSimple())
                 .setVmScheduler(new VmSchedulerTimeShared());

cloudsim-plus/pom.xml

@@ -4,7 +4,7 @@
 
     <groupId>org.cloudsimplus</groupId>
     <artifactId>cloudsim-plus</artifactId>
-    <version>2.1.0</version>
+    <version>2.2.0</version>
     <name>CloudSim Plus API</name>
     <description>CloudSim Plus: A modern, highly extensible and easier-to-use Java 8 Framework for Modeling and Simulation of Cloud Computing Infrastructures and Services</description>
     <url>http://cloudsimplus.org</url>

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/allocationpolicies/migration/VmAllocationPolicyMigrationAbstract.java

@@ -231,7 +231,7 @@ private void printOverUtilizedHosts(final Set<Host> overloadedHosts) {
     protected double getPowerAfterAllocationDifference(final Host host, final Vm vm){
         final double powerAfterAllocation = getPowerAfterAllocation(host, vm);
         if (powerAfterAllocation > 0) {
-            return powerAfterAllocation - host.getPowerSupply().getPower();
+            return powerAfterAllocation - host.getPowerModel().getPower();
         }
 
         return 0;
@@ -614,7 +614,7 @@ protected void restoreAllocation() {
      */
     protected double getPowerAfterAllocation(final Host host, final Vm vm) {
         try {
-            return host.getPowerSupply().getPowerModel().getPower(getMaxUtilizationAfterAllocation(host, vm));
+            return host.getPowerModel().getPower(getMaxUtilizationAfterAllocation(host, vm));
         } catch (Exception e) {
             Log.printFormattedLine("[ERROR] Power consumption for Host %d could not be determined: ", host.getId(), e.getMessage());
         }

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/core/CloudSim.java

@@ -35,7 +35,7 @@ public class CloudSim implements Simulation {
     /**
      * CloudSim Plus current version.
      */
-    public static final String VERSION = "2.1.0";
+    public static final String VERSION = "2.2.0";
 
     /**
      * An array that works as a circular queue with capacity for just 2 elements

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/datacenters/Datacenter.java

@@ -8,6 +8,7 @@
 package org.cloudbus.cloudsim.datacenters;
 
 import org.cloudbus.cloudsim.hosts.Host;
+import org.cloudbus.cloudsim.power.models.PowerModel;
 import org.cloudbus.cloudsim.vms.Vm;
 import org.cloudbus.cloudsim.cloudlets.Cloudlet;
 import org.cloudbus.cloudsim.core.SimEntity;
@@ -35,6 +36,12 @@ public interface Datacenter extends SimEntity {
      * {@link Datacenter} objects.
      */
     Datacenter NULL = new DatacenterNull();
+    /**
+     * The default percentage of bandwidth allocated for VM migration, is
+     * a value is not set.
+     * @see #setBandwidthPercentForMigration(double)
+     */
+    double DEF_BANDWIDTH_PERCENT_FOR_MIGRATION = 0.5;
 
     /**
      * Adds a file into the resource's storage before the experiment starts. If
@@ -176,4 +183,25 @@ public interface Datacenter extends SimEntity {
      * @param bandwidthPercentForMigration the bandwidth migration percentage to set
      */
     void setBandwidthPercentForMigration(double bandwidthPercentForMigration);
+
+    /**
+     * Gets an <b>estimation</b> of Datacenter power consumption (in Watts/Second).
+     * <p>To get actual power consumption, it's required to enable
+     * {@link Host#getStateHistory() Host's StateHistory}
+     * by calling {@link Host#enableStateHistory()}
+     * and use each Host {@link PowerModel} to compute power usage
+     * based on the CPU utilization got form the StateHistory.
+     * </p>
+     *
+     * @return th <b>estimated</b> power consumption (in Watts/Second)
+     */
+    double getPower();
+
+    /**
+     * Gets an <b>estimation</b> the Datacenter power consumption (in Kilo Watts/Hour).
+     *
+     * @return the <b>estimated</b> power consumption (in Kilo Watts/Hour)
+     * @see #getPower()
+     */
+    double getPowerInKWattsHour();
 }

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/datacenters/DatacenterNull.java

@@ -63,6 +63,8 @@ final class DatacenterNull implements Datacenter {
     }
     @Override public double getBandwidthPercentForMigration() { return 0; }
     @Override public void setBandwidthPercentForMigration(double bandwidthPercentForMigration) {/**/}
+    @Override public double getPower() { return 0; }
+    @Override public double getPowerInKWattsHour() { return 0; }
     @Override public SimEntity setState(State state) { return SimEntity.NULL; }
     @Override public boolean isStarted() { return false; }
     @Override public Simulation getSimulation() { return Simulation.NULL; }

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/datacenters/DatacenterSimple.java

@@ -11,6 +11,7 @@
 import org.cloudbus.cloudsim.core.events.SimEvent;
 import org.cloudbus.cloudsim.core.predicates.PredicateType;
 import org.cloudbus.cloudsim.network.IcmpPacket;
+import org.cloudbus.cloudsim.power.models.PowerModel;
 import org.cloudbus.cloudsim.util.Conversion;
 import org.cloudbus.cloudsim.util.DataCloudTags;
 import org.cloudbus.cloudsim.hosts.Host;
@@ -39,12 +40,6 @@
  * @since CloudSim Toolkit 1.0
  */
 public class DatacenterSimple extends CloudSimEntity implements Datacenter {
-    /**
-     * The default percentage of bandwidth allocated for VM migration, is
-     * a value is not set.
-     * @see #setBandwidthPercentForMigration(double)
-     */
-    private static final double DEF_BANDWIDTH_PERCENT_FOR_MIGRATION = 0.5;
 
     /**
      * @see #getBandwidthPercentForMigration()
@@ -725,10 +720,11 @@ protected double updateHostsProcessing() {
     }
 
     /**
-     * Gets the total power consumed (in Watts/sec) by all Hosts of the Datacenter since the last time the processing
-     * of Cloudlets in this Host was updated.
+     * Gets an <b>estimation</b> of total power consumed (in Watts/sec) by all Hosts of the Datacenter
+     * since the last time the processing of Cloudlets in this Host was updated.
      *
-     * @return the total power consumed (in Watts/sec) by all Hosts in the elapsed time span
+     * @return the <b>estimated</b> total power consumed (in Watts/sec) by all Hosts in the elapsed time span
+     * @see #getPower()
      */
     private double getDatacenterPowerUsageForTimeSpan() {
         if (getSimulation().clock() - getLastProcessTime() == 0) { //time span
@@ -740,7 +736,7 @@ private double getDatacenterPowerUsageForTimeSpan() {
             final double prevCpuUsage = host.getPreviousUtilizationOfCpu();
             final double cpuUsage = host.getUtilizationOfCpu();
             final double timeFrameHostEnergy =
-                host.getPowerSupply().getEnergyLinearInterpolation(prevCpuUsage, cpuUsage, getSimulation().clock() - getLastProcessTime());
+                host.getPowerModel().getEnergyLinearInterpolation(prevCpuUsage, cpuUsage, getSimulation().clock() - getLastProcessTime());
             datacenterTimeSpanPowerUse += timeFrameHostEnergy;
         }
 
@@ -1148,20 +1144,12 @@ public void setBandwidthPercentForMigration(final double bandwidthPercentForMigr
         this.bandwidthPercentForMigration = bandwidthPercentForMigration;
     }
 
-    /**
-     * Gets the Datacenter power consumption (in Watts/Second).
-     *
-     * @return the power consumption (in Watts/Second)
-     */
+    @Override
     public double getPower() {
         return power;
     }
 
-    /**
-     * Gets the Datacenter power consumption (in Kilo Watts/Hour).
-     *
-     * @return the power consumption (in Kilo Watts/Hour)
-     */
+    @Override
     public double getPowerInKWattsHour() {
         return getPower() / (3600 * 1000);
     }

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/hosts/Host.java

@@ -8,7 +8,6 @@
 package org.cloudbus.cloudsim.hosts;
 
 import org.cloudbus.cloudsim.core.Machine;
-import org.cloudbus.cloudsim.power.supply.PowerSupply;
 import org.cloudbus.cloudsim.power.models.PowerModel;
 import org.cloudbus.cloudsim.resources.*;
 import org.cloudbus.cloudsim.vms.Vm;
@@ -512,13 +511,23 @@ public interface Host extends Machine, Comparable<Host> {
     double[] getUtilizationHistory();
 
     /**
-     * Gets the {@link PowerSupply} that enables getting power usage information,
-     * including the {@link PowerModel}.
-     * Power information is just available if a {@link PowerModel} is set to the PowerSupply.
+     * Gets the {@link PowerModel} used by the host
+     * to define how it consumes power.
+     * A Host just provides power usage data if a PowerModel is set.
      *
+     * @return the Host's {@link PowerModel}
+     */
+    PowerModel getPowerModel();
+
+    /**
+     * Sets the {@link PowerModel} used by the host
+     * to define how it consumes power.
+     * A Host just provides power usage data if a PowerModel is set.
+     *
+     * @param powerModel the {@link PowerModel} to set
      * @return
      */
-    PowerSupply getPowerSupply();
+    Host setPowerModel(PowerModel powerModel);
 
     double getPreviousUtilizationOfCpu();
 

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/hosts/HostNull.java

@@ -2,7 +2,7 @@
 
 import org.cloudbus.cloudsim.core.Simulation;
 import org.cloudbus.cloudsim.datacenters.Datacenter;
-import org.cloudbus.cloudsim.power.supply.PowerSupply;
+import org.cloudbus.cloudsim.power.models.PowerModel;
 import org.cloudbus.cloudsim.provisioners.ResourceProvisioner;
 import org.cloudbus.cloudsim.resources.Pe;
 import org.cloudbus.cloudsim.resources.Resource;
@@ -97,9 +97,7 @@ final class HostNull implements Host {
         return Vm.NULL;
     }
     @Override public <T extends Vm> List<T> getVmCreatedList() { return Collections.EMPTY_LIST; }
-    @Override public List<Vm> getVmList() {
-        return Collections.emptyList();
-    }
+    @Override public List<Vm> getVmList() { return Collections.emptyList(); }
     @Override public VmScheduler getVmScheduler() {
         return VmScheduler.NULL;
     }
@@ -165,7 +163,8 @@ final class HostNull implements Host {
     @Override public long getUtilizationOfBw() { return 0; }
     @Override public long getUtilizationOfRam() { return 0; }
     @Override public double[] getUtilizationHistory() { return new double[0]; }
-    @Override public PowerSupply getPowerSupply() { return PowerSupply.NULL; }
+    @Override public PowerModel getPowerModel() { return PowerModel.NULL; }
+    @Override public Host setPowerModel(PowerModel powerModel) { return this; }
     @Override public double getPreviousUtilizationOfCpu() { return 0; }
     @Override public void enableStateHistory() {/**/}
     @Override public void disableStateHistory() {/**/}

cloudsim-plus/src/main/java/org/cloudbus/cloudsim/hosts/HostSimple.java

@@ -6,8 +6,7 @@
  */
 package org.cloudbus.cloudsim.hosts;
 
-import org.cloudbus.cloudsim.power.supply.HostPowerSupply;
-import org.cloudbus.cloudsim.power.supply.PowerSupply;
+import org.cloudbus.cloudsim.power.models.PowerModel;
 import org.cloudbus.cloudsim.resources.*;
 import org.cloudbus.cloudsim.util.Log;
 import org.cloudbus.cloudsim.util.MathUtil;
@@ -45,7 +44,7 @@ public class HostSimple implements Host {
      * @see #getStateHistory()
      */
     private final List<HostStateHistoryEntry> stateHistory;
-    private final PowerSupply powerSupply;
+    private PowerModel powerModel;
 
     /**
      * @see #getId()
@@ -167,7 +166,7 @@ public HostSimple(final long ram, final long bw, final long storage, final List<
         this.provisioners = new ArrayList<>();
         this.vmsMigratingIn = new HashSet<>();
         this.vmsMigratingOut = new HashSet<>();
-        this.powerSupply = new HostPowerSupply(this);
+        this.powerModel = PowerModel.NULL;
         stateHistory = new LinkedList<>();
     }
 
@@ -806,8 +805,20 @@ public double[] getUtilizationHistory() {
     }
 
     @Override
-    public PowerSupply getPowerSupply() {
-        return powerSupply;
+    public PowerModel getPowerModel() {
+        return powerModel;
+    }
+
+    @Override
+    public Host setPowerModel(final PowerModel powerModel) {
+        Objects.requireNonNull(powerModel);
+        if(powerModel.getHost() != null && powerModel.getHost() != Host.NULL && !powerModel.getHost().equals(this)){
+            throw new IllegalStateException("The given PowerModel is already assigned to another Host. Each Host must have its own PowerModel instance.");
+        }
+
+        this.powerModel = powerModel;
+        powerModel.setHost(this);
+        return this;
     }
 
     @Override
@@ -901,7 +912,7 @@ private void addStateHistory(final double currentTime) {
             hostTotalRequestedMips += totalRequestedMips;
         }
 
-        addStateHistoryEntry(currentTime, getUtilizationOfCpuMips(), hostTotalRequestedMips,getUtilizationOfCpuMips() > 0);
+        addStateHistoryEntry(currentTime, getUtilizationOfCpuMips(), hostTotalRequestedMips, active);
     }
 
     /**