uk.ac.starlink.ttools.task

Interface DynamicTask

All Known Implementing Classes:

AbstractPlot2Task, CubePlot2Task, GenericPlot2Task, MatrixPlot2Task, PlanePlot2Task, SkyPlot2Task, SpherePlot2Task, TimePlot2Task, TypedPlot2Task

public interface DynamicTask

Extends the Task interface by methods which allow task parameters to be queried based on a (at least partially) populated Environment. By default, Tasks report the Parameters they use so that the on-line help system can supply that information to users at runtime. However, for some tasks the parameters in use depend on the value of other parameters. This interface allows tasks to make that information available. The method implementations are considered to be on a best-efforts basis, it is not guaranteed that they will be able to report all the parameters. This information is only used for user help.

Since:

19 Sep 2014

Author:

Mark Taylor

Method Summary

Modifier and Type	Method and Description
Parameter<?>[]	getContextParameters(Environment env) Returns the parameters for this task in the context of a given execution environment.
Parameter<?>	getParameterByName(Environment env, String paramName) Attempts to find a parameter with a given name that might be used by this task in the content of the given environment.

Method Detail

getParameterByName

Parameter<?> getParameterByName(Environment env,
                                String paramName)
                         throws TaskException

Attempts to find a parameter with a given name that might be used by this task in the content of the given environment.

This ought not to result in additional prompts to the user.

Parameters:

env - execution environment

paramName - requested parameter name

Returns:

parameter with the given name, or null

Throws:

TaskException

getContextParameters

Parameter<?>[] getContextParameters(Environment env)
                             throws TaskException

Returns the parameters for this task in the context of a given execution environment. If the environment is empty, this should give the same result as Task.getParameters(), but found settings of parameters in the presented environment may lead to parameters being added to or removed from the list.

This ought not to result in additional prompts to the user.

Parameters:

env - execution environment

Returns:

list of known parameters

Throws:

TaskException