Parameter (ELKI: Environment for DeveLoping KDD-Applications Supported by Index-Structures)

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

All Known Implementing Classes:

AbstractParameter, ClassListParameter, ClassParameter, DoubleListParameter, DoubleParameter, DynamicParameters.RemainingOptions, EnumParameter, FileListParameter, FileParameter, Flag, IntListParameter, IntParameter, ListParameter, LongParameter, NumberParameter, ObjectListParameter, ObjectParameter, PatternParameter, RandomParameter, StringParameter, VectorListParameter
```
public interface Parameter<T>
```
Interface for the parameter of a class. A parameter is defined as an option having a specific value. See the de.lmu.ifi.dbs.elki.utilities.optionhandling package for documentation!

Author:

Steffi Wanka, Erich Schubert

Method Summary

Methods
Modifier and Type	Method and Description
`Parameter<T>`	`addConstraint(ParameterConstraint<? super T> constraint)` Add an additional constraint.
`T`	`getDefaultValue()` Returns the default value of the parameter.
`String`	`getDefaultValueAsString()` Get the default value as string.
`String`	`getFullDescription()` Returns the extended description of the option which includes the option's type, the short description and the default value (if specified).
`Object`	`getGivenValue()` Get the last given value.
`String`	`getName()` Returns the name of the option.
`OptionID`	`getOptionID()` Return the OptionID of this option.
`String`	`getShortDescription()` Returns the short description of the option.
`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.
`String`	`getValueAsString()` Get the value as string.
`String`	`getValuesDescription()` Return a string explaining valid values.
`boolean`	`hasDefaultValue()` Checks if this parameter has a default value.
`boolean`	`hasValuesDescription()` Whether this class has a list of default values.
`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(Object obj)` Checks if the given argument is valid for this option.
`Parameter<T>`	`setDefaultValue(T defaultValue)` Sets the default value of this parameter.
`Parameter<T>`	`setOptional(boolean opt)` Specifies if this parameter is an optional parameter.
`void`	`setShortDescription(String description)` Sets the short description of the option.
`void`	`setValue(Object obj)` Sets the value of the option.
`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.
`void`	`useDefaultValue()` Sets the default value of this parameter as the actual value of this parameter.

- Method Detail
  - setDefaultValue
```
Parameter<T> setDefaultValue(T defaultValue)
```
    Sets the default value of this parameter.
    
    Parameters:
    defaultValue - default value of this parameter
    
    Returns:
    the parameter itself, for chaining
  - hasDefaultValue
```
boolean hasDefaultValue()
```
    Checks if this parameter has a default value.
    
    Returns:
    true, if this parameter has a default value, false otherwise
  - useDefaultValue
```
void useDefaultValue()
```
    Sets the default value of this parameter as the actual value of this parameter.
  - tryDefaultValue
```
boolean tryDefaultValue()
                        throws UnspecifiedParameterException
```
    Handle default values for a parameter.
    
    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
```
Parameter<T> setOptional(boolean opt)
```
    Specifies if this parameter is an optional parameter.
    
    Parameters:
    opt - true if this parameter is optional, false otherwise
    
    Returns:
    the parameter itself, for chaining
  - isOptional
```
boolean isOptional()
```
    Checks if this parameter is an optional parameter.
    
    Returns:
    true if this parameter is optional, false otherwise
  - tookDefaultValue
```
boolean tookDefaultValue()
```
    Checks if the default value of this parameter was taken as the actual parameter value.
    
    Returns:
    true, if the default value was taken as actual parameter value, false otherwise
  - isDefined
```
boolean isDefined()
```
    Returns true if the value of the option is defined, false otherwise.
    
    Returns:
    true if the value of the option is defined, false otherwise.
  - getDefaultValue
```
T getDefaultValue()
```
    Returns the default value of the parameter.
    If the parameter has no default value, the method returns null.
    
    Returns:
    the default value of the parameter, null if the parameter has no default value.
  - hasValuesDescription
```
boolean hasValuesDescription()
```
    Whether this class has a list of default values.
    
    Returns:
    whether the class has a description of valid values.
  - getValuesDescription
```
String getValuesDescription()
```
    Return a string explaining valid values.
    
    Returns:
    String explaining valid values (e.g. a class list)
  - getFullDescription
```
String getFullDescription()
```
    Returns the extended description of the option which includes the option's type, the short description and the default value (if specified).
    
    Returns:
    the option's description.
  - getOptionID
```
OptionID getOptionID()
```
    Return the OptionID of this option.
    
    Returns:
    Option ID
  - getName
```
String getName()
```
    Returns the name of the option.
    
    Returns:
    the option's name.
  - getShortDescription
```
String getShortDescription()
```
    Returns the short description of the option.
    
    Returns:
    the option's short description.
  - setShortDescription
```
void setShortDescription(String description)
```
    Sets the short description of the option.
    
    Parameters:
    description - the short description to be set
  - setValue
```
void setValue(Object obj)
              throws ParameterException
```
    Sets the value of the option.
    
    Parameters:
    obj - the option's value to be set
    
    Throws:
    
    ParameterException - if the given value is not a valid value for this option.
  - getValue
```
T getValue()
```
    Returns the value of the option. You should use either Parameterization.grab(de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.Parameter<?>) or isDefined() to test if getValue() will return a well-defined value.
    
    Returns:
    the option's value.
  - getGivenValue
```
Object getGivenValue()
```
    Get the last given value. May return null
    
    Returns:
    Given value
  - isValid
```
boolean isValid(Object obj)
                throws ParameterException
```
    Checks if the given argument is valid for this option.
    
    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
```
String getSyntax()
```
    Returns a string representation of the parameter's type (e.g. an IntParameter should return <int>).
    
    Returns:
    a string representation of the parameter's type
  - getValueAsString
```
String getValueAsString()
```
    Get the value as string. May return null
    
    Returns:
    Value as string
  - getDefaultValueAsString
```
String getDefaultValueAsString()
```
    Get the default value as string.
    
    Returns:
    default value
  - addConstraint
```
Parameter<T> addConstraint(ParameterConstraint<? super T> constraint)
```
    Add an additional constraint.
    
    Parameters:
    constraint - Constraint to add.
    
    Returns:
    the parameter itself, for chaining

Interface Parameter<T>

Method Summary

Method Detail

setDefaultValue

hasDefaultValue

useDefaultValue

tryDefaultValue

setOptional

isOptional

tookDefaultValue

isDefined

getDefaultValue

hasValuesDescription

getValuesDescription

getFullDescription

getOptionID

getName

getShortDescription

setShortDescription

setValue

getValue

getGivenValue

isValid

getSyntax

getValueAsString

getDefaultValueAsString

addConstraint