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, respectsNull, setConditionIndex, 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()