private void attachPattern(
final BuildContext context, final BuildUtils utils, final Pattern pattern)
throws InvalidPatternException {
// Set pattern offset to the appropriate value
pattern.setOffset(context.getCurrentPatternOffset());
final List<Constraint> alphaConstraints = new LinkedList<Constraint>();
final List<Constraint> betaConstraints = new LinkedList<Constraint>();
final List<Behavior> behaviors = new LinkedList<Behavior>();
this.createConstraints(context, utils, pattern, alphaConstraints, betaConstraints);
// Create BetaConstraints object
context.setBetaconstraints(betaConstraints);
// set behaviors list
behaviors.addAll(pattern.getBehaviors());
context.setBehaviors(behaviors);
if (pattern.getSource() != null) {
context.setAlphaConstraints(alphaConstraints);
final int currentOffset = context.getCurrentPatternOffset();
PatternSource source = pattern.getSource();
ReteooComponentBuilder builder = utils.getBuilderFor(source);
builder.build(context, utils, source);
// restoring offset
context.setCurrentPatternOffset(currentOffset);
}
if (pattern.getSource() == null || context.getCurrentEntryPoint() != EntryPoint.DEFAULT) {
attachAlphaNodes(context, utils, pattern, alphaConstraints);
if (context.getCurrentEntryPoint() != EntryPoint.DEFAULT) {
context.setObjectSource(
(ObjectSource)
utils.attachNode(
context,
new PropagationQueuingNode(
context.getNextId(), context.getObjectSource(), context)));
// the entry-point specific network nodes are attached, so, set context to default
// entry-point
context.setCurrentEntryPoint(EntryPoint.DEFAULT);
}
}
// last thing to do is increment the offset, since if the pattern has a source,
// offset must be overriden
context.incrementCurrentPatternOffset();
}
public void attachAlphaNodes(
final BuildContext context,
final BuildUtils utils,
final Pattern pattern,
List<Constraint> alphaConstraints)
throws InvalidPatternException {
// Drools Query ObjectTypeNode never has memory, but other ObjectTypeNode/AlphaNoesNodes may (if
// not in sequential),
// so need to preserve, so we can restore after this node is added. LeftMemory and Terminal
// remain the same once set.
boolean objectMemory = context.isObjectTypeNodeMemoryEnabled();
boolean alphaMemory = context.isAlphaMemoryAllowed();
ObjectType objectType = pattern.getObjectType();
if (pattern.getObjectType() instanceof ClassObjectType) {
// Is this the query node, if so we don't want any memory
if (DroolsQuery.class == ((ClassObjectType) pattern.getObjectType()).getClassType()) {
context.setTupleMemoryEnabled(false);
context.setObjectTypeNodeMemoryEnabled(false);
context.setTerminalNodeMemoryEnabled(false);
context.setAlphaNodeMemoryAllowed(false);
}
}
context.setObjectSource(
(ObjectSource)
utils.attachNode(
context,
new EntryPointNode(context.getNextId(), context.getRuleBase().getRete(), context)));
ObjectTypeNode otn =
new ObjectTypeNode(
context.getNextId(), (EntryPointNode) context.getObjectSource(), objectType, context);
if (objectType.isEvent()
&& EventProcessingOption.STREAM.equals(
context.getRuleBase().getConfiguration().getEventProcessingMode())) {
long expirationOffset = getExpiratioOffsetForType(context, objectType);
if (expirationOffset != -1) {
// expiration policy is set, so use it
otn.setExpirationOffset(expirationOffset);
} else {
// otherwise calculate it based on behaviours and temporal constraints
for (Behavior behavior : pattern.getBehaviors()) {
if (behavior.getExpirationOffset() != -1) {
expirationOffset = Math.max(behavior.getExpirationOffset(), expirationOffset);
}
}
long distance = context.getTemporalDistance().getExpirationOffset(pattern);
if (distance == -1) {
// it means the rules have no temporal constraints, or
// the constraints require events to be hold forever. In this
// case, we allow type declarations to override the implicit
// expiration offset by defining an expiration policy with the
// @expires tag
otn.setExpirationOffset(expirationOffset);
} else {
otn.setExpirationOffset(Math.max(distance, expirationOffset));
}
}
}
context.setObjectSource((ObjectSource) utils.attachNode(context, otn));
for (final Iterator<Constraint> it = alphaConstraints.iterator(); it.hasNext(); ) {
final AlphaNodeFieldConstraint constraint = (AlphaNodeFieldConstraint) it.next();
context.pushRuleComponent(constraint);
context.setObjectSource(
(ObjectSource)
utils.attachNode(
context,
new AlphaNode(
context.getNextId(),
(AlphaNodeFieldConstraint) constraint,
context.getObjectSource(),
context)));
context.popRuleComponent();
}
// now restore back to original values
context.setObjectTypeNodeMemoryEnabled(objectMemory);
context.setAlphaNodeMemoryAllowed(alphaMemory);
}