net.esper.eql.core
Class AggregationServiceFactory

java.lang.Object
  extended by net.esper.eql.core.AggregationServiceFactory

public class AggregationServiceFactory
extends Object

Factory for aggregation service instances.


Constructor Summary
AggregationServiceFactory()
           
 
Method Summary
static AggregationService getService(List<ExprAggregateNode> aggregateExprNodes, boolean hasGroupByClause, ExprNode optionalHavingNode, List<ExprNode> sortByNodes)
          Returns an instance to handle the aggregation required by the aggregation expression nodes, depending on whether there are any group-by nodes.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

AggregationServiceFactory

public AggregationServiceFactory()
Method Detail

getService

public static AggregationService getService(List<ExprAggregateNode> aggregateExprNodes,
                                            boolean hasGroupByClause,
                                            ExprNode optionalHavingNode,
                                            List<ExprNode> sortByNodes)
Returns an instance to handle the aggregation required by the aggregation expression nodes, depending on whether there are any group-by nodes.

Parameters:
aggregateExprNodes - - aggregation nodes extracted out of the select expression
hasGroupByClause - - indicator on whethere there is group-by required, or group-all
optionalHavingNode - - having node if having-clause was specified, or null if no having-clause given
sortByNodes - - the nodes for the sort-by clause
Returns:
instance for aggregation handling