Package com.espertech.esper.common.internal.epl.pattern.core

Class EvalStateNode

java.lang.Object
com.espertech.esper.common.internal.epl.pattern.core.EvalStateNode
Direct Known Subclasses:
EvalAndStateNode, EvalEveryDistinctStateExpireKeyNode, EvalEveryDistinctStateNode, EvalEveryStateNode, EvalFilterStateNode, EvalFollowedByStateNode, EvalFollowedByWithMaxStateNodeManaged, EvalGuardStateNode, EvalMatchUntilStateNode, EvalNotStateNode, EvalObserverStateNode, EvalOrStateNode, EvalRootStateNode
public abstract class EvalStateNode extends Object
Superclass of all state nodes in an evaluation node tree representing an event expressions. Follows the Composite pattern. Subclasses are expected to keep their own collection containing child nodes as needed.

  • Constructor Details

    • EvalStateNode

      public EvalStateNode(Evaluator parentNode)
      Constructor.
      Parameters:
      parentNode - is the evaluator for this node on which to indicate a change in truth value

  • Method Details

    • start

      public abstract void start(MatchedEventMap beginState)
      Starts the event expression or an instance of it. Child classes are expected to initialize and start any event listeners or schedule any time-based callbacks as needed.
      Parameters:
      beginState - begin state

    • quit

      public abstract void quit()
      Stops the event expression or an instance of it. Child classes are expected to free resources and stop any event listeners or remove any time-based callbacks.

    • accept

      public abstract void accept(EvalStateNodeVisitor visitor)
      Accept a visitor. Child classes are expected to invoke the visit method on the visitor instance passed in.
      Parameters:
      visitor - on which the visit method is invoked by each node

    • getFactoryNode

      public abstract EvalNode getFactoryNode()
      Returns the factory node for the state node.
      Returns:
      factory node

    • isNotOperator

      public abstract boolean isNotOperator()

    • isFilterStateNode

      public abstract boolean isFilterStateNode()

    • isObserverStateNodeNonRestarting

      public abstract boolean isObserverStateNodeNonRestarting()

    • removeMatch

      public abstract void removeMatch(Set<EventBean> matchEvent)
      Remove matches that overlap with the provided events.
      Parameters:
      matchEvent - set of events to check for

    • transfer

      public void transfer(AgentInstanceTransferServices services)

    • getParentEvaluator

      public final Evaluator getParentEvaluator()
      Returns the parent evaluator.
      Returns:
      parent evaluator instance

    • setParentEvaluator

      public final void setParentEvaluator(Evaluator parentEvaluator)
      Sets the parent evaluator.
      Parameters:
      parentEvaluator - for this node