Class MulticastRelOptListener

java.lang.Object
org.apache.calcite.plan.MulticastRelOptListener
All Implemented Interfaces:
EventListener, RelOptListener

public class MulticastRelOptListener extends Object implements RelOptListener
MulticastRelOptListener implements the RelOptListener interface by forwarding events on to a collection of other listeners.
  • Constructor Details

    • MulticastRelOptListener

      public MulticastRelOptListener()
      Creates a new empty multicast listener.
  • Method Details

    • addListener

      public void addListener(RelOptListener listener)
      Adds a listener which will receive multicast events.
      Parameters:
      listener - listener to add
    • relEquivalenceFound

      public void relEquivalenceFound(RelOptListener.RelEquivalenceEvent event)
      Description copied from interface: RelOptListener
      Notifies this listener that a relational expression has been registered with a particular equivalence class after an equivalence has been either detected or asserted. Equivalence classes may be either logical (all expressions which yield the same result set) or physical (all expressions which yield the same result set with a particular calling convention).
      Specified by:
      relEquivalenceFound in interface RelOptListener
      Parameters:
      event - details about the event
    • ruleAttempted

      public void ruleAttempted(RelOptListener.RuleAttemptedEvent event)
      Description copied from interface: RelOptListener
      Notifies this listener that an optimizer rule is being applied to a particular relational expression. This rule is called twice; once before the rule is invoked, and once after. Note that the rel attribute of the event is always the old expression.
      Specified by:
      ruleAttempted in interface RelOptListener
      Parameters:
      event - details about the event
    • ruleProductionSucceeded

      public void ruleProductionSucceeded(RelOptListener.RuleProductionEvent event)
      Description copied from interface: RelOptListener
      Notifies this listener that an optimizer rule has been successfully applied to a particular relational expression, resulting in a new equivalent expression (relEquivalenceFound will also be called unless the new expression is identical to an existing one). This rule is called twice; once before registration of the new rel, and once after. Note that the rel attribute of the event is always the new expression; to get the old expression, use event.getRuleCall().rels[0].
      Specified by:
      ruleProductionSucceeded in interface RelOptListener
      Parameters:
      event - details about the event
    • relChosen

      public void relChosen(RelOptListener.RelChosenEvent event)
      Description copied from interface: RelOptListener
      Notifies this listener that a relational expression has been chosen as part of the final implementation of the query plan. After the plan is complete, this is called one more time with null for the rel.
      Specified by:
      relChosen in interface RelOptListener
      Parameters:
      event - details about the event
    • relDiscarded

      public void relDiscarded(RelOptListener.RelDiscardedEvent event)
      Description copied from interface: RelOptListener
      Notifies this listener that a relational expression is no longer of interest to the planner.
      Specified by:
      relDiscarded in interface RelOptListener
      Parameters:
      event - details about the event