uk.ac.starlink.task

Class ObjectFactoryParameter<T>

java.lang.Object

uk.ac.starlink.task.Parameter<T>

uk.ac.starlink.task.ObjectFactoryParameter<T>

Direct Known Subclasses:

OutputModeParameter

public class ObjectFactoryParameter<T>
extends Parameter<T>

Parameter whose (user-supplied) string values correspond to nicknames from an ObjectFactory. The Parameter.objectValue(uk.ac.starlink.task.Environment) method returns the corresponding object generated by the factory for that nickname.

Since:

22 Nov 2006

Author:

Mark Taylor

Field Summary

Fields inherited from class uk.ac.starlink.task.Parameter

BY_NAME

Constructor Summary

Constructors

Constructor and Description
ObjectFactoryParameter(String name, ObjectFactory<T> factory) Constructor.

Method Summary

Modifier and Type	Method and Description
ObjectFactory<T>	getObjectFactory() Returns the object factory used by this parameter.
String	getUsage() Returns the usage string for this parameter.
T	stringToObject(Environment env, String sval) Takes a non-blank string, as supplied by the execution environment, and turns it into a typed value for this parameter.

Methods inherited from class uk.ac.starlink.task.Parameter

clearValue, getDescription, getName, getPosition, getPreferExplicit, getPrompt, getStringDefault, getValueClass, isNullPermitted, objectToString, objectValue, setDescription, setDescription, setName, setNullPermitted, setPosition, setPreferExplicit, setPrompt, setStringDefault, setUsage, setValue, setValueFromObject, setValueFromString, stringValue, toArray, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectFactoryParameter

public ObjectFactoryParameter(String name,
                              ObjectFactory<T> factory)

Constructor.

Parameters:

name - parameter name

factory - object factory

Method Detail

getObjectFactory

public ObjectFactory<T> getObjectFactory()

Returns the object factory used by this parameter.

Returns:

object factory

stringToObject

public T stringToObject(Environment env,
                        String sval)
                 throws ParameterValueException

Description copied from class: Parameter

Takes a non-blank string, as supplied by the execution environment, and turns it into a typed value for this parameter. This method also performs validation, so if the string value is unacceptable in any way, a ParameterValueException should be thrown.

It is an error to supply a null or empty string value.

If this method fails (throws a ParameterValueException) and if allowClassnameValue is set, then a subsequent attempt will be made to interpret the stringVal as the classname of a suitable class with a no-arg constructor.

Specified by:

stringToObject in class Parameter<T>

Parameters:

env - execution environment; in most cases this is not required but for some purposes environment-specific characteristics may influence the result

sval - non-null, non-empty string value

Returns:

typed value

Throws:

ParameterValueException

getUsage

public String getUsage()

Description copied from class: Parameter

Returns the usage string for this parameter.

Overrides:

getUsage in class Parameter<T>

Returns:

usage string

See Also:

Parameter.setUsage(java.lang.String)