/*
***************************************************************************************
* Copyright (C) 2006 EsperTech, Inc. All rights reserved. *
* http://www.espertech.com/esper *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
***************************************************************************************
*/
package com.espertech.esper.epl.view;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.core.context.util.AgentInstanceContext;
import com.espertech.esper.core.service.EPStatementHandleCallback;
import com.espertech.esper.core.service.EngineLevelExtensionServicesContext;
import com.espertech.esper.epl.expression.core.ExprEvaluator;
import com.espertech.esper.epl.variable.VariableChangeCallback;
import com.espertech.esper.event.arr.ObjectArrayEventBean;
import com.espertech.esper.metrics.instrumentation.InstrumentationHelper;
import com.espertech.esper.schedule.ScheduleHandleCallback;
import com.espertech.esper.util.ExecutionPathDebugLog;
import com.espertech.esper.util.StopCallback;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Output condition for output rate limiting that handles when-then expressions for controlling output.
*/
public class OutputConditionExpression extends OutputConditionBase implements OutputCondition, VariableChangeCallback, StopCallback {
private static final Logger log = LoggerFactory.getLogger(OutputConditionExpression.class);
private final AgentInstanceContext agentInstanceContext;
private final OutputConditionExpressionFactory parent;
private final long scheduleSlot;
private boolean isCallbackScheduled;
private boolean ignoreVariableCallbacks;
private ObjectArrayEventBean builtinProperties;
private EventBean[] eventsPerStream;
// ongoing builtin properties
private int totalNewEventsCount;
private int totalOldEventsCount;
private int totalNewEventsSum;
private int totalOldEventsSum;
private Long lastOutputTimestamp;
private EPStatementHandleCallback scheduleHandle;
public OutputConditionExpression(OutputCallback outputCallback, final AgentInstanceContext agentInstanceContext, OutputConditionExpressionFactory parent, boolean isStartConditionOnCreation) {
super(outputCallback);
this.agentInstanceContext = agentInstanceContext;
this.parent = parent;
scheduleSlot = agentInstanceContext.getStatementContext().getScheduleBucket().allocateSlot();
this.eventsPerStream = new EventBean[1];
if (parent.getBuiltinPropertiesEventType() != null) {
builtinProperties = new ObjectArrayEventBean(OutputConditionExpressionTypeUtil.getOAPrototype(), parent.getBuiltinPropertiesEventType());
lastOutputTimestamp = agentInstanceContext.getStatementContext().getSchedulingService().getTime();
}
if (parent.getVariableNames() != null) {
// if using variables, register a callback on the change of the variable
for (String variableName : parent.getVariableNames()) {
final String theVariableName = variableName;
agentInstanceContext.getStatementContext().getVariableService().registerCallback(variableName, agentInstanceContext.getAgentInstanceId(), this);
agentInstanceContext.addTerminationCallback(new StopCallback() {
public void stop() {
agentInstanceContext.getStatementContext().getVariableService().unregisterCallback(theVariableName, agentInstanceContext.getAgentInstanceId(), OutputConditionExpression.this);
}
});
}
}
if (isStartConditionOnCreation) {
update(0, 0);
}
}
public void updateOutputCondition(int newEventsCount, int oldEventsCount) {
this.totalNewEventsCount += newEventsCount;
this.totalOldEventsCount += oldEventsCount;
this.totalNewEventsSum += newEventsCount;
this.totalOldEventsSum += oldEventsCount;
boolean isOutput = evaluate(parent.getWhenExpressionNodeEval());
if (isOutput) {
executeThenAssignments();
outputCallback.continueOutputProcessing(true, true);
resetBuiltinProperties();
}
}
public void update(Object newValue, Object oldValue) {
if (ignoreVariableCallbacks) {
log.debug(".update Ignoring variable callback");
return;
}
agentInstanceContext.getStatementContext().getVariableService().setLocalVersion();
boolean isOutput = evaluate(parent.getWhenExpressionNodeEval());
if (isOutput && (!isCallbackScheduled)) {
scheduleCallback();
}
}
public void stop() {
if (scheduleHandle != null) {
agentInstanceContext.getStatementContext().getSchedulingService().remove(scheduleHandle, scheduleSlot);
scheduleHandle = null;
}
}
@Override
public void terminated() {
boolean output = true;
if (parent.getAndWhenTerminatedExpressionNodeEval() != null) {
output = evaluate(parent.getAndWhenTerminatedExpressionNodeEval());
}
if (parent.getVariableReadWritePackageAfterTerminated() != null) {
if (builtinProperties != null) {
populateBuiltinProps();
eventsPerStream[0] = builtinProperties;
}
ignoreVariableCallbacks = true;
try {
parent.getVariableReadWritePackageAfterTerminated().writeVariables(agentInstanceContext.getStatementContext().getVariableService(), eventsPerStream, null, agentInstanceContext);
} finally {
ignoreVariableCallbacks = false;
}
}
if (output) {
super.terminated();
}
}
private boolean evaluate(ExprEvaluator evaluator) {
if (builtinProperties != null) {
populateBuiltinProps();
eventsPerStream[0] = builtinProperties;
}
boolean result = false;
Boolean output = (Boolean) evaluator.evaluate(eventsPerStream, true, agentInstanceContext);
if ((output != null) && output) {
result = true;
}
return result;
}
private void scheduleCallback() {
isCallbackScheduled = true;
long current = agentInstanceContext.getStatementContext().getSchedulingService().getTime();
if ((ExecutionPathDebugLog.isDebugEnabled) && (log.isDebugEnabled())) {
log.debug(".scheduleCallback Scheduled new callback for " +
" afterMsec=" + 0 +
" now=" + current);
}
ScheduleHandleCallback callback = new ScheduleHandleCallback() {
public void scheduledTrigger(EngineLevelExtensionServicesContext extensionServicesContext) {
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().qOutputRateConditionScheduledEval();
}
OutputConditionExpression.this.isCallbackScheduled = false;
OutputConditionExpression.this.outputCallback.continueOutputProcessing(true, true);
resetBuiltinProperties();
if (InstrumentationHelper.ENABLED) {
InstrumentationHelper.get().aOutputRateConditionScheduledEval();
}
}
};
scheduleHandle = new EPStatementHandleCallback(agentInstanceContext.getEpStatementAgentInstanceHandle(), callback);
agentInstanceContext.getStatementContext().getSchedulingService().add(0, scheduleHandle, scheduleSlot);
agentInstanceContext.addTerminationCallback(this);
// execute assignments
executeThenAssignments();
}
private void executeThenAssignments() {
if (parent.getVariableReadWritePackage() != null) {
if (builtinProperties != null) {
populateBuiltinProps();
eventsPerStream[0] = builtinProperties;
}
ignoreVariableCallbacks = true;
try {
parent.getVariableReadWritePackage().writeVariables(agentInstanceContext.getStatementContext().getVariableService(), eventsPerStream, null, agentInstanceContext);
} finally {
ignoreVariableCallbacks = false;
}
}
}
private void resetBuiltinProperties() {
if (builtinProperties != null) {
totalNewEventsCount = 0;
totalOldEventsCount = 0;
lastOutputTimestamp = agentInstanceContext.getStatementContext().getSchedulingService().getTime();
}
}
private void populateBuiltinProps() {
OutputConditionExpressionTypeUtil.populate(builtinProperties.getProperties(), totalNewEventsCount, totalOldEventsCount, totalNewEventsSum, totalOldEventsSum, lastOutputTimestamp);
}
}