org.datanucleus.query.evaluator.memory
Class SetExpression

java.lang.Object
  org.datanucleus.query.evaluator.memory.SetExpression

public class SetExpression
extends java.lang.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 subtypes for Java type handling.

Constructor Summary

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

Method Summary

java.lang.Object	avg(Expression paramExpr, ExpressionEvaluator eval, SymbolTable symtbl)
java.lang.Object	count(Expression expr, ExpressionEvaluator eval)
java.lang.Object	max(Expression paramExpr, ExpressionEvaluator eval, SymbolTable symtbl)
java.lang.Object	min(Expression paramExpr, ExpressionEvaluator eval, SymbolTable symtbl)
java.lang.Object	sum(Expression paramExpr, ExpressionEvaluator eval, SymbolTable symtbl)

Methods inherited from class java.lang.Object

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

Constructor Detail

SetExpression

public SetExpression(java.util.Collection items,
                     java.lang.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 java.lang.Object count(Expression expr,
                              ExpressionEvaluator eval)

min

public java.lang.Object min(Expression paramExpr,
                            ExpressionEvaluator eval,
                            SymbolTable symtbl)

max

public java.lang.Object max(Expression paramExpr,
                            ExpressionEvaluator eval,
                            SymbolTable symtbl)

sum

public java.lang.Object sum(Expression paramExpr,
                            ExpressionEvaluator eval,
                            SymbolTable symtbl)

avg

public java.lang.Object avg(Expression paramExpr,
                            ExpressionEvaluator eval,
                            SymbolTable symtbl)