de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters

Class AbstractParameter<THIS extends AbstractParameter<THIS,T>,T>

java.lang.Object

de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.AbstractParameter<THIS,T>

Type Parameters:

THIS - type self-reference

T - the type of a possible value (i.e., the type of the option)

All Implemented Interfaces:

Parameter<T>

Direct Known Subclasses:

ClassParameter, EnumParameter, FileParameter, Flag, IntGeneratorParameter, ListParameter, NumberParameter, PatternParameter, RandomParameter, StringParameter

public abstract class AbstractParameter<THIS extends AbstractParameter<THIS,T>,T>
extends java.lang.Object
implements Parameter<T>

Abstract class for specifying a parameter. A parameter is defined as an option having a specific value. See the de.lmu.ifi.dbs.elki.utilities.optionhandling package for documentation!

Since:

0.1

Author:

Steffi Wanka, Erich Schubert

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.List<ParameterConstraint<? super T>>	constraints Holds parameter constraints for this parameter.
protected T	defaultValue The default value of the parameter (may be null).
private boolean	defaultValueTaken Specifies if the default value of this parameter was taken as parameter value.
protected T	givenValue The value last passed to this option.
protected boolean	optionalParameter Specifies if this parameter is an optional parameter.
protected OptionID	optionid The option name.
protected java.lang.String	shortDescription The short description of the option.
private T	value The value of this option.

Constructor Summary

Constructors

Constructor and Description
AbstractParameter(OptionID optionID) Constructs a parameter with the given optionID, and constraints.
AbstractParameter(OptionID optionID, boolean optional) Constructs a parameter with the given optionID, constraints, and optional flag.
AbstractParameter(OptionID optionID, T defaultValue) Constructs a parameter with the given optionID, constraints, and default value.

Method Summary

Modifier and Type	Method and Description
THIS	addConstraint(ParameterConstraint<? super T> constraint) Add an additional constraint.
java.lang.StringBuilder	describeValues(java.lang.StringBuilder description) Describe the valid values.
java.util.List<ParameterConstraint<? super T>>	getConstraints() Get the parameter constraints.
T	getDefaultValue() Returns the default value of the parameter.
java.lang.String	getDefaultValueAsString() Get the default value as string.
OptionID	getOptionID() Return the OptionID of this option.
java.lang.String	getShortDescription() Returns the short description of the option.
abstract java.lang.String	getSyntax() Returns a string representation of the parameter's type (e.g. an IntParameter should return <int>).
T	getValue() Returns the value of the option.
abstract java.lang.String	getValueAsString() Get the value as string.
boolean	hasDefaultValue() Checks if this parameter has a default value.
boolean	isDefined() Returns true if the value of the option is defined, false otherwise.
boolean	isOptional() Checks if this parameter is an optional parameter.
boolean	isValid(java.lang.Object obj) Checks if the given argument is valid for this option.
protected abstract T	parseValue(java.lang.Object obj) Parse a given value into the destination type.
THIS	setDefaultValue(T defaultValue) Sets the default value of this parameter.
THIS	setOptional(boolean opt) Specifies if this parameter is an optional parameter.
void	setShortDescription(java.lang.String description) Sets the short description of the option.
void	setValue(java.lang.Object obj) Sets the value of the option.
protected void	setValueInternal(T val) Internal setter for the value.
boolean	tookDefaultValue() Checks if the default value of this parameter was taken as the actual parameter value.
boolean	tryDefaultValue() Handle default values for a parameter.
protected boolean	validate(T obj) Validate a value after parsing (e.g. do constraint checks!)

Methods inherited from class java.lang.Object

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

Field Detail

defaultValue

protected T defaultValue

The default value of the parameter (may be null).

defaultValueTaken

private boolean defaultValueTaken

Specifies if the default value of this parameter was taken as parameter value.

optionalParameter

protected boolean optionalParameter

Specifies if this parameter is an optional parameter.

constraints

protected java.util.List<ParameterConstraint<? super T>> constraints

Holds parameter constraints for this parameter.

optionid

protected final OptionID optionid

The option name.

shortDescription

protected java.lang.String shortDescription

The short description of the option.

givenValue

protected T givenValue

The value last passed to this option.

value

private T value

The value of this option.

Constructor Detail

AbstractParameter

public AbstractParameter(OptionID optionID,
                         T defaultValue)

Constructs a parameter with the given optionID, constraints, and default value.

Parameters:

optionID - the unique id of this parameter

defaultValue - the default value of this parameter (may be null)

AbstractParameter

public AbstractParameter(OptionID optionID,
                         boolean optional)

Constructs a parameter with the given optionID, constraints, and optional flag.

Parameters:

optionID - the unique id of this parameter

optional - specifies if this parameter is an optional parameter

AbstractParameter

public AbstractParameter(OptionID optionID)

Constructs a parameter with the given optionID, and constraints.

Parameters:

optionID - the unique id of this parameter

Method Detail

setDefaultValue

public THIS setDefaultValue(T defaultValue)

Description copied from interface: Parameter

Sets the default value of this parameter.

Specified by:

setDefaultValue in interface Parameter<T>

Parameters:

defaultValue - default value of this parameter

Returns:

the parameter itself, for chaining

hasDefaultValue

public boolean hasDefaultValue()

Description copied from interface: Parameter

Checks if this parameter has a default value.

Specified by:

hasDefaultValue in interface Parameter<T>

Returns:

true, if this parameter has a default value, false otherwise

tryDefaultValue

public boolean tryDefaultValue()
                        throws UnspecifiedParameterException

Description copied from interface: Parameter

Handle default values for a parameter.

Specified by:

tryDefaultValue in interface Parameter<T>

Returns:

Return code: true if it has a default value, false if it is optional without a default value. Exception if it is a required parameter!

Throws:

UnspecifiedParameterException - If the parameter requires a value

setOptional

public THIS setOptional(boolean opt)

Description copied from interface: Parameter

Specifies if this parameter is an optional parameter.

Specified by:

setOptional in interface Parameter<T>

Parameters:

opt - true if this parameter is optional, false otherwise

Returns:

the parameter itself, for chaining

isOptional

public boolean isOptional()

Description copied from interface: Parameter

Checks if this parameter is an optional parameter.

Specified by:

isOptional in interface Parameter<T>

Returns:

true if this parameter is optional, false otherwise

tookDefaultValue

public boolean tookDefaultValue()

Description copied from interface: Parameter

Checks if the default value of this parameter was taken as the actual parameter value.

Specified by:

tookDefaultValue in interface Parameter<T>

Returns:

true, if the default value was taken as actual parameter value, false otherwise

isDefined

public boolean isDefined()

Description copied from interface: Parameter

Returns true if the value of the option is defined, false otherwise.

Specified by:

isDefined in interface Parameter<T>

Returns:

true if the value of the option is defined, false otherwise.

getDefaultValue

public T getDefaultValue()

Description copied from interface: Parameter

Returns the default value of the parameter.

If the parameter has no default value, the method returns null.

Specified by:

getDefaultValue in interface Parameter<T>

Returns:

the default value of the parameter, null if the parameter has no default value.

describeValues

public java.lang.StringBuilder describeValues(java.lang.StringBuilder description)

Description copied from interface: Parameter

Describe the valid values.

Specified by:

describeValues in interface Parameter<T>

Parameters:

description - Buffer to append to

Returns:

Buffer

validate

protected boolean validate(T obj)
                    throws ParameterException

Validate a value after parsing (e.g. do constraint checks!)

Parameters:

obj - Object to validate

Returns:

true iff the object is valid for this parameter.

Throws:

ParameterException - when the object is not valid.

getOptionID

public OptionID getOptionID()

Description copied from interface: Parameter

Return the OptionID of this option.

Specified by:

getOptionID in interface Parameter<T>

Returns:

Option ID

getShortDescription

public java.lang.String getShortDescription()

Description copied from interface: Parameter

Returns the short description of the option.

Specified by:

getShortDescription in interface Parameter<T>

Returns:

the option's short description.

setShortDescription

public void setShortDescription(java.lang.String description)

Description copied from interface: Parameter

Sets the short description of the option.

Specified by:

setShortDescription in interface Parameter<T>

Parameters:

description - the short description to be set

setValue

public void setValue(java.lang.Object obj)
              throws ParameterException

Description copied from interface: Parameter

Sets the value of the option.

Specified by:

setValue in interface Parameter<T>

Parameters:

obj - the option's value to be set

Throws:

ParameterException - if the given value is not a valid value for this option.

setValueInternal

protected final void setValueInternal(T val)

Internal setter for the value.

Parameters:

val - Value

getValue

public final T getValue()

Description copied from interface: Parameter

Returns the value of the option. You should use either Parameterization.grab(de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.Parameter<?>) or Parameter.isDefined() to test if getValue() will return a well-defined value.

Specified by:

getValue in interface Parameter<T>

Returns:

the option's value.

isValid

public final boolean isValid(java.lang.Object obj)
                      throws ParameterException

Description copied from interface: Parameter

Checks if the given argument is valid for this option.

Specified by:

isValid in interface Parameter<T>

Parameters:

obj - option value to be checked

Returns:

true, if the given value is valid for this option

Throws:

ParameterException - if the given value is not a valid value for this option.

getSyntax

public abstract java.lang.String getSyntax()

Description copied from interface: Parameter

Returns a string representation of the parameter's type (e.g. an IntParameter should return <int>).

Specified by:

getSyntax in interface Parameter<T>

Returns:

a string representation of the parameter's type

parseValue

protected abstract T parseValue(java.lang.Object obj)
                         throws ParameterException

Parse a given value into the destination type.

Parameters:

obj - Object to parse (may be a string representation!)

Returns:

Parsed object

Throws:

ParameterException - when the object cannot be parsed.

getValueAsString

public abstract java.lang.String getValueAsString()

Description copied from interface: Parameter

Get the value as string. May return null

Specified by:

getValueAsString in interface Parameter<T>

Returns:

Value as string

getDefaultValueAsString

public java.lang.String getDefaultValueAsString()

Description copied from interface: Parameter

Get the default value as string.

Specified by:

getDefaultValueAsString in interface Parameter<T>

Returns:

default value

addConstraint

public THIS addConstraint(ParameterConstraint<? super T> constraint)

Description copied from interface: Parameter

Add an additional constraint.

Specified by:

addConstraint in interface Parameter<T>

Parameters:

constraint - Constraint to add.

Returns:

the parameter itself, for chaining

getConstraints

public java.util.List<ParameterConstraint<? super T>> getConstraints()

Description copied from interface: Parameter

Get the parameter constraints.

Specified by:

getConstraints in interface Parameter<T>

Returns:

Parameter constraints