Package org.datanucleus.store.query.inmemory

Class SetExpression

java.lang.Object

org.datanucleus.store.query.inmemory.SetExpression

public class SetExpression
extends Object

Expression for the aggregation of a set of object values. Provides basic aggregation methods "count", "min", "max", "avg", "sum" and makes use of the AggregateExpression sub-types for Java type handling.

Constructor Summary

Constructors

Constructor	Description
SetExpression(Collection items, String alias)	Constructor for a SetExpression to perform the aggregation.

Method Summary

Modifier and Type	Method	Description
Object	avg(Expression paramExpr, ExpressionEvaluator eval, Map<String,Object> state)
Object	count(Expression expr, ExpressionEvaluator eval)
Object	max(Expression paramExpr, ExpressionEvaluator eval, Map<String,Object> state)
Object	min(Expression paramExpr, ExpressionEvaluator eval, Map<String,Object> state)
Object	sum(Expression paramExpr, ExpressionEvaluator eval, Map<String,Object> state)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SetExpression

public SetExpression(Collection items,
                     String alias)

Constructor for a SetExpression to perform the aggregation.

Parameters:

items - The items to aggregate

alias - The alias for these items

Method Detail

count

public Object count(Expression expr,
                    ExpressionEvaluator eval)

min

public Object min(Expression paramExpr,
                  ExpressionEvaluator eval,
                  Map<String,Object> state)

max

public Object max(Expression paramExpr,
                  ExpressionEvaluator eval,
                  Map<String,Object> state)

sum

public Object sum(Expression paramExpr,
                  ExpressionEvaluator eval,
                  Map<String,Object> state)

avg

public Object avg(Expression paramExpr,
                  ExpressionEvaluator eval,
                  Map<String,Object> state)