/**
* Ctor.
*
* @param assignments the list of variable assignments
* @param variableService variable service
* @param eventAdapterService event adapters
* @throws com.espertech.esper.epl.expression.core.ExprValidationException when variables cannot
* be found
*/
public VariableReadWritePackage(
List<OnTriggerSetAssignment> assignments,
VariableService variableService,
EventAdapterService eventAdapterService)
throws ExprValidationException {
this.metaData = new VariableMetaData[assignments.size()];
this.readersForGlobalVars = new VariableReader[assignments.size()];
this.mustCoerce = new boolean[assignments.size()];
this.writers = new WriteDesc[assignments.size()];
this.variableTypes = new HashMap<String, Object>();
this.eventAdapterService = eventAdapterService;
this.variableService = variableService;
Map<EventTypeSPI, CopyMethodDesc> eventTypeWrittenProps =
new HashMap<EventTypeSPI, CopyMethodDesc>();
int count = 0;
List<VariableTriggerSetDesc> assignmentList = new ArrayList<VariableTriggerSetDesc>();
for (OnTriggerSetAssignment expressionWithAssignments : assignments) {
Pair<String, ExprNode> possibleVariableAssignment =
ExprNodeUtility.checkGetAssignmentToVariableOrProp(
expressionWithAssignments.getExpression());
if (possibleVariableAssignment == null) {
throw new ExprValidationException(
"Missing variable assignment expression in assignment number " + count);
}
assignmentList.add(
new VariableTriggerSetDesc(
possibleVariableAssignment.getFirst(),
possibleVariableAssignment.getSecond().getExprEvaluator()));
String fullVariableName = possibleVariableAssignment.getFirst();
String variableName = fullVariableName;
String subPropertyName = null;
int indexOfDot = variableName.indexOf('.');
if (indexOfDot != -1) {
subPropertyName = variableName.substring(indexOfDot + 1, variableName.length());
variableName = variableName.substring(0, indexOfDot);
}
VariableMetaData variableMetadata = variableService.getVariableMetaData(variableName);
metaData[count] = variableMetadata;
if (variableMetadata == null) {
throw new ExprValidationException(
"Variable by name '" + variableName + "' has not been created or configured");
}
if (variableMetadata.isConstant()) {
throw new ExprValidationException(
"Variable by name '" + variableName + "' is declared constant and may not be set");
}
if (variableMetadata.getContextPartitionName() == null) {
readersForGlobalVars[count] =
variableService.getReader(variableName, VariableService.NOCONTEXT_AGENTINSTANCEID);
}
if (subPropertyName != null) {
if (variableMetadata.getEventType() == null) {
throw new ExprValidationException(
"Variable by name '"
+ variableName
+ "' does not have a property named '"
+ subPropertyName
+ "'");
}
EventType type = variableMetadata.getEventType();
if (!(type instanceof EventTypeSPI)) {
throw new ExprValidationException(
"Variable by name '"
+ variableName
+ "' event type '"
+ type.getName()
+ "' not writable");
}
EventTypeSPI spi = (EventTypeSPI) type;
EventPropertyWriter writer = spi.getWriter(subPropertyName);
EventPropertyGetter getter = spi.getGetter(subPropertyName);
if (writer == null) {
throw new ExprValidationException(
"Variable by name '"
+ variableName
+ "' the property '"
+ subPropertyName
+ "' is not writable");
}
variableTypes.put(fullVariableName, spi.getPropertyType(subPropertyName));
CopyMethodDesc writtenProps = eventTypeWrittenProps.get(spi);
if (writtenProps == null) {
writtenProps = new CopyMethodDesc(variableName, new ArrayList<String>());
eventTypeWrittenProps.put(spi, writtenProps);
}
writtenProps.getPropertiesCopied().add(subPropertyName);
writers[count] = new WriteDesc(spi, variableName, writer, getter);
} else {
// determine types
Class expressionType = possibleVariableAssignment.getSecond().getExprEvaluator().getType();
if (variableMetadata.getEventType() != null) {
if ((expressionType != null)
&& (!JavaClassHelper.isSubclassOrImplementsInterface(
expressionType, variableMetadata.getEventType().getUnderlyingType()))) {
throw new VariableValueException(
"Variable '"
+ variableName
+ "' of declared event type '"
+ variableMetadata.getEventType().getName()
+ "' underlying type '"
+ variableMetadata.getEventType().getUnderlyingType().getName()
+ "' cannot be assigned a value of type '"
+ expressionType.getName()
+ "'");
}
variableTypes.put(variableName, variableMetadata.getEventType().getUnderlyingType());
} else {
Class variableType = variableMetadata.getType();
variableTypes.put(variableName, variableType);
// determine if the expression type can be assigned
if (variableType != java.lang.Object.class) {
if ((JavaClassHelper.getBoxedType(expressionType) != variableType)
&& (expressionType != null)) {
if ((!JavaClassHelper.isNumeric(variableType))
|| (!JavaClassHelper.isNumeric(expressionType))) {
throw new ExprValidationException(
VariableServiceUtil.getAssigmentExMessage(
variableName, variableType, expressionType));
}
if (!(JavaClassHelper.canCoerce(expressionType, variableType))) {
throw new ExprValidationException(
VariableServiceUtil.getAssigmentExMessage(
variableName, variableType, expressionType));
}
mustCoerce[count] = true;
}
}
}
}
count++;
}
this.assignments = assignmentList.toArray(new VariableTriggerSetDesc[assignmentList.size()]);
if (eventTypeWrittenProps.isEmpty()) {
copyMethods = Collections.EMPTY_MAP;
return;
}
copyMethods = new HashMap<EventTypeSPI, EventBeanCopyMethod>();
for (Map.Entry<EventTypeSPI, CopyMethodDesc> entry : eventTypeWrittenProps.entrySet()) {
List<String> propsWritten = entry.getValue().getPropertiesCopied();
String[] props = propsWritten.toArray(new String[propsWritten.size()]);
EventBeanCopyMethod copyMethod = entry.getKey().getCopyMethod(props);
if (copyMethod == null) {
throw new ExprValidationException(
"Variable '"
+ entry.getValue().getVariableName()
+ "' of declared type "
+ JavaClassHelper.getClassNameFullyQualPretty(entry.getKey().getUnderlyingType())
+ "' cannot be assigned to");
}
copyMethods.put(entry.getKey(), copyMethod);
}
}
/**
* Write new variable values and commit, evaluating assignment expressions using the given events
* per stream.
*
* <p>Populates an optional map of new values if a non-null map is passed.
*
* @param variableService variable service
* @param eventsPerStream events per stream
* @param valuesWritten null or an empty map to populate with written values
* @param exprEvaluatorContext expression evaluation context
*/
public void writeVariables(
VariableService variableService,
EventBean[] eventsPerStream,
Map<String, Object> valuesWritten,
ExprEvaluatorContext exprEvaluatorContext) {
Set<String> variablesBeansCopied = null;
if (!copyMethods.isEmpty()) {
variablesBeansCopied = new HashSet<String>();
}
// We obtain a write lock global to the variable space
// Since expressions can contain variables themselves, these need to be unchangeable for the
// duration
// as there could be multiple statements that do "var1 = var1 + 1".
variableService.getReadWriteLock().writeLock().lock();
try {
variableService.setLocalVersion();
int count = 0;
for (VariableTriggerSetDesc assignment : assignments) {
VariableMetaData variableMetaData = metaData[count];
int agentInstanceId =
variableMetaData.getContextPartitionName() == null
? VariableService.NOCONTEXT_AGENTINSTANCEID
: exprEvaluatorContext.getAgentInstanceId();
Object value = assignment.evaluator.evaluate(eventsPerStream, true, exprEvaluatorContext);
if (writers[count] != null) {
VariableReader reader =
variableService.getReader(
variableMetaData.getVariableName(), exprEvaluatorContext.getAgentInstanceId());
EventBean current = (EventBean) reader.getValue();
if (current == null) {
value = null;
} else {
WriteDesc writeDesc = writers[count];
boolean copy = variablesBeansCopied.add(writeDesc.getVariableName());
if (copy) {
EventBean copied = copyMethods.get(writeDesc.getType()).copy(current);
current = copied;
}
variableService.write(variableMetaData.getVariableNumber(), agentInstanceId, current);
writeDesc.getWriter().write(value, current);
}
} else if (variableMetaData.getEventType() != null) {
EventBean eventBean =
eventAdapterService.adapterForType(value, variableMetaData.getEventType());
variableService.write(variableMetaData.getVariableNumber(), agentInstanceId, eventBean);
} else {
if ((value != null) && (mustCoerce[count])) {
value = JavaClassHelper.coerceBoxed((Number) value, variableMetaData.getType());
}
variableService.write(variableMetaData.getVariableNumber(), agentInstanceId, value);
}
count++;
if (valuesWritten != null) {
valuesWritten.put(assignment.variableName, value);
}
}
variableService.commit();
} catch (RuntimeException ex) {
log.error("Error evaluating on-set variable expressions: " + ex.getMessage(), ex);
variableService.rollback();
} finally {
variableService.getReadWriteLock().writeLock().unlock();
}
}