com.espertech.esper.common.client.hook.aggfunc

Interface AggregationFunction

public interface AggregationFunction

Maintains aggregation state applying values as entering and leaving the state.

Implementations must also act as a factory for further independent copies of aggregation states such that new aggregation state holders and be created from a prototype.

Field Summary

Fields

Modifier and Type	Field and Description
static EPTypeClass	EPTYPE Type information.

Method Summary

Modifier and Type	Method and Description
void	clear() Clear out the collection.
void	enter(java.lang.Object value) Apply the value as entering aggregation (entering window).
java.lang.Object	getValue() Returns the current value held.
void	leave(java.lang.Object value) Apply the value as leaving aggregation (leaving window).

Field Detail

EPTYPE

static final EPTypeClass EPTYPE

Type information.

Method Detail

enter

void enter(java.lang.Object value)

Apply the value as entering aggregation (entering window).

The value can be null since 'null' values may be counted as unique separate values.

Parameters:

value - to add to aggregate

leave

void leave(java.lang.Object value)

Apply the value as leaving aggregation (leaving window).

The value can be null since 'null' values may be counted as unique separate values.

Parameters:

value - to remove from aggregate

getValue

java.lang.Object getValue()

Returns the current value held.

Returns:

current value

clear

void clear()

Clear out the collection.