com.metamatrix.query.function.aggregate
Class Sum

java.lang.Object
  com.metamatrix.query.function.aggregate.Sum

All Implemented Interfaces:

AggregateFunction

Direct Known Subclasses:

Avg

public class Sum
extends java.lang.Object
implements AggregateFunction

Accumulates (per tuple) and calculates the sum of the values of a column. The type of the result varies depending on the type of the input AggregateSymbol

Field Summary

protected int	accumulatorType
protected static int	BIG_DECIMAL
protected static int	BIG_INTEGER
protected static int	DOUBLE
protected static int	LONG

Constructor Summary

Sum()
Constructor for Sum.

Method Summary

void	addInput(java.lang.Object input) Called for the element value in every row of a group.
protected int	getAccumulatorType() Allows subclasses to determine type of accumulator for the SUM.
java.lang.Object	getResult() Called after all values have been processed to get the result.
void	initialize(java.lang.Class dataType) Called to initialize the function.
void	reset() Called to reset the state of the function.

Methods inherited from class java.lang.Object

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

Field Detail

LONG

protected static final int LONG

See Also:

Constant Field Values

DOUBLE

protected static final int DOUBLE

See Also:

Constant Field Values

BIG_INTEGER

protected static final int BIG_INTEGER

See Also:

Constant Field Values

BIG_DECIMAL

protected static final int BIG_DECIMAL

See Also:

Constant Field Values

accumulatorType

protected int accumulatorType

Constructor Detail

Sum

public Sum()

Constructor for Sum.

Method Detail

getAccumulatorType

protected int getAccumulatorType()

Allows subclasses to determine type of accumulator for the SUM.

Returns:

Type, as defined in constants

initialize

public void initialize(java.lang.Class dataType)

Description copied from interface: AggregateFunction

Called to initialize the function. In the future this may expand with additional information.

Specified by:

initialize in interface AggregateFunction

Parameters:

dataType - Data type of element begin aggregated

See Also:

com.metamatrix.query.function.aggregate.AggregateFunction#initialize(boolean, String)

reset

public void reset()

Description copied from interface: AggregateFunction

Called to reset the state of the function.

Specified by:

reset in interface AggregateFunction

addInput

public void addInput(java.lang.Object input)
              throws FunctionExecutionException,
                     ExpressionEvaluationException,
                     MetaMatrixComponentException

Description copied from interface: AggregateFunction

Called for the element value in every row of a group.

Specified by:

addInput in interface AggregateFunction

Parameters:

input - Input value, may be null

Throws:

FunctionExecutionException

ExpressionEvaluationException

MetaMatrixComponentException

See Also:

AggregateFunction.addInput(Object)

getResult

public java.lang.Object getResult()
                           throws FunctionExecutionException,
                                  ExpressionEvaluationException,
                                  MetaMatrixComponentException

Description copied from interface: AggregateFunction

Called after all values have been processed to get the result.

Specified by:

getResult in interface AggregateFunction

Returns:

Result value

Throws:

FunctionExecutionException

ExpressionEvaluationException

MetaMatrixComponentException

See Also:

AggregateFunction.getResult()