org.teiid.query.function.aggregate
Class Avg

java.lang.Object
  org.teiid.query.function.aggregate.AggregateFunction
      org.teiid.query.function.aggregate.Sum
          org.teiid.query.function.aggregate.Avg

public class Avg
extends Sum

Accumulates (per tuple) and calculates the average of the values of a column. The type of the result varies depending on the type of the input AggregateSymbol - the type will not be an integral type but will always be some kind of decimal type.

Field Summary

Fields inherited from class org.teiid.query.function.aggregate.Sum

accumulatorType, BIG_DECIMAL, BIG_INTEGER, DOUBLE, LONG

Constructor Summary

Avg()

Method Summary

void	addInputDirect(java.lang.Object input, java.util.List<?> tuple) Called for the element value in every row of a group.
java.lang.Object	getResult() Called after all values have been processed to get the result.
void	initialize(java.lang.Class<?> dataType, java.lang.Class<?> inputType) Called to initialize the function.
void	reset() Called to reset the state of the function.

Methods inherited from class org.teiid.query.function.aggregate.Sum

getAccumulatorType

Methods inherited from class org.teiid.query.function.aggregate.AggregateFunction

addInput, setExpressionIndex

Methods inherited from class java.lang.Object

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

Constructor Detail

Avg

public Avg()

Method Detail

initialize

public void initialize(java.lang.Class<?> dataType,
                       java.lang.Class<?> inputType)

Description copied from class: AggregateFunction

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

Overrides:

initialize in class Sum

Parameters:

dataType - Data type of element begin aggregated

See Also:

org.teiid.query.function.aggregate.AggregateFunction#initialize(String, Class)

reset

public void reset()

Description copied from class: AggregateFunction

Called to reset the state of the function.

Overrides:

reset in class Sum

addInputDirect

public void addInputDirect(java.lang.Object input,
                           java.util.List<?> tuple)
                    throws FunctionExecutionException,
                           ExpressionEvaluationException,
                           TeiidComponentException

Description copied from class: AggregateFunction

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

Overrides:

addInputDirect in class Sum

Parameters:

input - Input value, may be null

Throws:

FunctionExecutionException

ExpressionEvaluationException

TeiidComponentException

See Also:

AggregateFunction.addInputDirect(Object, List)

getResult

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

Description copied from class: AggregateFunction

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

Overrides:

getResult in class Sum

Returns:

Result value

Throws:

FunctionExecutionException

ExpressionEvaluationException

TeiidComponentException

See Also:

AggregateFunction.getResult()