[Major] Refactored the DurationExecutionTimer to not be singleton

Once again it is clear how bad singletons are. One test killed the
timer, thus all other tests failed. Now the DelayedExecutionTimer is
retrieved from the ExecutionHandler and is called DelayedExecutionTimer
with a default implementation of SimpleDurationExecutionTimer
instantiated by the EventBasedExecutionHandler

li.strolch.rest/src/main/java/li/strolch/rest/StrolchRestfulConstants.java

@@ -28,6 +28,7 @@ public class StrolchRestfulConstants {
 	public static final String LAST_OFFSET = "lastOffset";
 	public static final String NEXT_OFFSET = "nextOffset";
 	public static final String PREVIOUS_OFFSET = "previousOffset";
+	public static final String DATA_SET_SIZE = "dataSetSize";
 	public static final String SIZE = "size";
 	public static final String OFFSET = "offset";
 	public static final String LIMIT = "limit";

li.strolch.service/src/main/java/li/strolch/execution/DelayedExecutionTimer.java

@@ -0,0 +1,13 @@
+package li.strolch.execution;
+
+import li.strolch.agent.api.ComponentContainer;
+import li.strolch.model.Locator;
+
+public interface DelayedExecutionTimer {
+
+	void cancel(Locator locator);
+
+	void execute(String realm, ComponentContainer container, Locator locator, long duration);
+
+	void destroy();
+}

li.strolch.service/src/main/java/li/strolch/execution/EventBasedExecutionHandler.java

@@ -16,10 +16,31 @@ import li.strolch.privilege.model.PrivilegeContext;
 
 public class EventBasedExecutionHandler extends ExecutionHandler {
 
+	private DelayedExecutionTimer delayedExecutionTimer;
+
 	public EventBasedExecutionHandler(ComponentContainer container, String componentName) {
 		super(container, componentName);
 	}
 
+	@Override
+	public void start() throws Exception {
+
+		this.delayedExecutionTimer = new SimpleDurationExecutionTimer();
+
+		super.start();
+	}
+
+	@Override
+	public void stop() throws Exception {
+
+		if (this.delayedExecutionTimer != null) {
+			this.delayedExecutionTimer.destroy();
+			this.delayedExecutionTimer = null;
+		}
+
+		super.stop();
+	}
+
 	@Override
 	public void toExecution(String realm, Locator locator) {
 		runAsAgent(ctx -> {
@@ -125,4 +146,9 @@ public class EventBasedExecutionHandler extends ExecutionHandler {
 	protected StrolchTransaction openTx(String realm, Certificate cert, Class<?> clazz) {
 		return getContainer().getRealm(realm).openTx(cert, clazz);
 	}
+
+	@Override
+	public DelayedExecutionTimer getDelayedExecutionTimer() {
+		return this.delayedExecutionTimer;
+	}
 }

li.strolch.service/src/main/java/li/strolch/execution/ExecutionHandler.java

@@ -9,6 +9,8 @@ public abstract class ExecutionHandler extends StrolchComponent {
 	public ExecutionHandler(ComponentContainer container, String componentName) {
 		super(container, componentName);
 	}
+	
+	public abstract DelayedExecutionTimer getDelayedExecutionTimer();
 
 	public abstract void toExecution(String realm, Locator locator);
 

li.strolch.service/src/main/java/li/strolch/execution/SimpleDurationExecutionTimer.java

@@ -11,28 +11,26 @@ import org.slf4j.LoggerFactory;
 import li.strolch.agent.api.ComponentContainer;
 import li.strolch.model.Locator;
 
-public class DurationExecutionTimer {
+public class SimpleDurationExecutionTimer implements DelayedExecutionTimer {
 
-	private static final Logger logger = LoggerFactory.getLogger(DurationExecutionTimer.class);
-
-	private static final DurationExecutionTimer instance;
-
-	static {
-		instance = new DurationExecutionTimer();
-	}
-
-	public static DurationExecutionTimer getInstance() {
-		return instance;
-	}
+	private static final Logger logger = LoggerFactory.getLogger(SimpleDurationExecutionTimer.class);
 
 	private Timer timer;
 
 	private Map<Locator, SimulationTask> simulationPolicies;
 
-	public DurationExecutionTimer() {
+	public SimpleDurationExecutionTimer() {
 		this.simulationPolicies = new HashMap<>();
 	}
 
+	@Override
+	public void destroy() {
+		if (this.timer != null) {
+			this.timer.cancel();
+		}
+	}
+
+	@Override
 	public void cancel(Locator locator) {
 		SimulationTask task = this.simulationPolicies.remove(locator);
 		if (task != null) {
@@ -40,6 +38,7 @@ public class DurationExecutionTimer {
 		}
 	}
 
+	@Override
 	public void execute(String realm, ComponentContainer container, Locator locator, long duration) {
 		if (this.timer == null)
 			this.timer = new Timer("SimulationExecution", true);

li.strolch.service/src/main/java/li/strolch/execution/policy/DurationExecution.java

@@ -2,7 +2,6 @@ package li.strolch.execution.policy;
 
 import li.strolch.agent.api.ComponentContainer;
 import li.strolch.command.UpdateActivityCommand;
-import li.strolch.execution.DurationExecutionTimer;
 import li.strolch.model.Locator;
 import li.strolch.model.State;
 import li.strolch.model.activity.Action;
@@ -33,7 +32,7 @@ public class DurationExecution extends ExecutionPolicy {
 		String realmName = tx().getRealmName();
 		Locator locator = action.getLocator();
 		logger.warn("Executing action " + action.getLocator() + " has a duration of " + durationP.getValueAsString());
-		DurationExecutionTimer.getInstance().execute(realmName, getContainer(), locator, durationP.getValue());
+		getDelayedExecutionTimer().execute(realmName, getContainer(), locator, durationP.getValue());
 
 		action.setState(State.EXECUTION);
 
@@ -59,7 +58,7 @@ public class DurationExecution extends ExecutionPolicy {
 	@Override
 	public void toStopped(Action action) {
 
-		DurationExecutionTimer.getInstance().cancel(action.getLocator());
+		getDelayedExecutionTimer().cancel(action.getLocator());
 
 		action.setState(State.STOPPED);
 
@@ -73,7 +72,7 @@ public class DurationExecution extends ExecutionPolicy {
 	@Override
 	public void toError(Action action) {
 
-		DurationExecutionTimer.getInstance().cancel(action.getLocator());
+		getDelayedExecutionTimer().cancel(action.getLocator());
 
 		action.setState(State.ERROR);
 

li.strolch.service/src/main/java/li/strolch/execution/policy/ExecutionPolicy.java

@@ -2,6 +2,8 @@ package li.strolch.execution.policy;
 
 import li.strolch.agent.api.ComponentContainer;
 import li.strolch.command.UpdateActivityCommand;
+import li.strolch.execution.DelayedExecutionTimer;
+import li.strolch.execution.ExecutionHandler;
 import li.strolch.model.State;
 import li.strolch.model.activity.Action;
 import li.strolch.persistence.api.StrolchTransaction;
@@ -31,4 +33,8 @@ public abstract class ExecutionPolicy extends StrolchPolicy {
 
 		logger.warn("Action " + action.getLocator() + " is now in WARNING!");
 	}
+
+	protected DelayedExecutionTimer getDelayedExecutionTimer() {
+		return getComponent(ExecutionHandler.class).getDelayedExecutionTimer();
+	}
 }