org.diirt.datasource.formula

Class DynamicFormulaFunction

java.lang.Object

org.diirt.datasource.formula.StatefulFormulaFunction

org.diirt.datasource.formula.DynamicFormulaFunction

All Implemented Interfaces:

FormulaFunction

Direct Known Subclasses:

CaHistogramFormulaFunction, ChannelFormulaFunction, ChannelsFormulaFunction

public abstract class DynamicFormulaFunction
extends StatefulFormulaFunction

Formula function that can dynamically add and remove access to channels.

This formula function is given a director which can be used to open/close expressions that read real-time data.

Author:

carcassi

Constructor Summary

Constructors

Constructor and Description
DynamicFormulaFunction()

Method Summary

Modifier and Type	Method and Description
<T> DesiredRateExpression<T>	channel(String channelName, Class clazz) Expression for the last value of the given channel, suitable to be used within formula.
PVDirector<?>	getDirector() The director to use to connect/disconnect live data expressions.

Methods inherited from class org.diirt.datasource.formula.StatefulFormulaFunction

dispose, isPure

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.diirt.datasource.formula.FormulaFunction

calculate, getArgumentNames, getArgumentTypes, getDescription, getName, getReturnType, isVarArgs

Constructor Detail

DynamicFormulaFunction

public DynamicFormulaFunction()

Method Detail

getDirector

public final PVDirector<?> getDirector()

The director to use to connect/disconnect live data expressions.

Returns:

the director

channel

public final <T> DesiredRateExpression<T> channel(String channelName,
                                                  Class clazz)

Expression for the last value of the given channel, suitable to be used within formula.

TODO: we need to clarify when it is better to use this method directly, and when to use the normal expressions.

Type Parameters:

T - the expression type

Parameters:

channelName - the channel name

clazz - the expression type

Returns:

a new expression