Module org.apache.sis.referencing

Package org.apache.sis.parameter

Class DefaultParameterDescriptor<T>

Object

FormattableObject

AbstractIdentifiedObject

AbstractParameterDescriptor

DefaultParameterDescriptor<T>

Type Parameters:

T - the type of elements to be returned by Default­Parameter­Value.get­Value().

All Implemented Interfaces:

Serializable, Formattable, Deprecable, Lenient­Comparable, General­Parameter­Descriptor, Parameter­Descriptor<T>, Identified­Object

public class DefaultParameterDescriptor<T>
extends AbstractParameterDescriptor
implements ParameterDescriptor<T>

The definition of a single parameter used by an operation method. For Coordinate Reference Systems most parameter values are numeric, but other types of parameter values are possible.

A parameter descriptor contains the following properties:

• The parameter name.
• The class of values. This is usually Double, double[], Integer, int[], Boolean, String or URI, but other types are allowed as well.
• Whether this parameter is optional or mandatory. This is specified by the minimum occurences number, which can be 0 or 1 respectively.
• The domain of values, as a minimum value, maximum value or an enumeration of valid values.
• The default value.
• The unit of measurement.

Since:

0.4

See Also:

• Default­Parameter­Value
• Default­Parameter­Descriptor­Group
• Serialized Form

Field Summary

Fields inherited from class AbstractIdentifiedObject

DEPRECATED_KEY, LOCALE_KEY

Fields inherited from interface IdentifiedObject

ALIAS_KEY, IDENTIFIERS_KEY, NAME_KEY, REMARKS_KEY

Constructor Summary

Constructors

Modifier	Constructor	Description
	Default­Parameter­Descriptor(Map<String,?> properties, int minimum­Occurs, int maximum­Occurs, Class<T> value­Class, Range<?> value­Domain, T[] valid­Values, T default­Value)	Constructs a descriptor from the given properties.
protected	Default­Parameter­Descriptor(Parameter­Descriptor<T> descriptor)	Creates a new descriptor with the same values than the specified one.

Method Summary

Modifier and Type	Method	Description
static <T> Default­Parameter­Descriptor<T>	cast­Or­Copy(Parameter­Descriptor<T> object)	Returns a SIS parameter implementation with the same values than the given arbitrary implementation.
protected long	compute­Hash­Code()	Invoked by Abstract­Identified­Object.hash­Code() for computing the hash code when first needed.
Parameter­Value<T>	create­Value()	Creates a new parameter value instance initialized with the default value.
boolean	equals(Object object, Comparison­Mode mode)	Compares the specified object with this parameter for equality.
T	get­Default­Value()	Returns the default value for the parameter.
Class<? extends Parameter­Descriptor<T>>	get­Interface()	Returns the GeoAPI interface implemented by this class.
Comparable<T>	get­Maximum­Value()	Returns the maximum parameter value.
Comparable<T>	get­Minimum­Value()	Returns the minimum parameter value.
Unit<?>	get­Unit()	Returns the unit of measurement for the minimum, maximum and default values.
Set<T>	get­Valid­Values()	If this parameter allows only a finite set of values, returns that set.
final Class<T>	get­Value­Class()	Returns the class that describes the type of parameter values.
final Range<?>	get­Value­Domain()	Returns the domain of values with their unit of measurement (if any), or null if none.
Type­Name	get­Value­Type()	Returns the name that describes the type of parameter values.

Methods inherited from class AbstractParameterDescriptor

format­To, get­Maximum­Occurs, get­Minimum­Occurs, print, to­String

Methods inherited from class AbstractIdentifiedObject

cast­Or­Copy, equals, format­To, get­Alias, get­Description, get­Domains, get­Identifiers, get­Name, get­Remarks, hash­Code, is­Deprecated, is­Heuristic­Match­For­Name

Methods inherited from class FormattableObject

to­String, to­WKT

Methods inherited from class Object

clone, finalize, get­Class, notify, notify­All, wait, wait, wait

Methods inherited from interface GeneralParameterDescriptor

get­Maximum­Occurs, get­Minimum­Occurs

Methods inherited from interface IdentifiedObject

get­Alias, get­Identifiers, get­Name, get­Remarks, to­WKT

Constructor Details

DefaultParameterDescriptor

public DefaultParameterDescriptor(Map<String,?> properties,
 int minimumOccurs,
 int maximumOccurs,
 Class<T> valueClass,
 Range<?> valueDomain,
 T[] validValues,
 T defaultValue)

Constructs a descriptor from the given properties. The properties map is given unchanged to the super-class constructor. The following table is a reminder of main (not all) properties:

Recognized properties (non exhaustive list)

Property name	Value type	Returned by
"name"	ReferenceIdentifier or String	AbstractIdentifiedObject.getName()
"alias"	GenericName or Char­Sequence (optionally as array)	AbstractIdentifiedObject.getAlias()
"identifiers"	ReferenceIdentifier (optionally as array)	AbstractIdentifiedObject.getIdentifiers()
"description"	InternationalString or String	AbstractIdentifiedObject.getDescription()
"remarks"	InternationalString or String	AbstractIdentifiedObject.getRemarks()

The value­Domain argument combines the minimum value, maximum value, unit of measurement (if any) and information about whether the bounds are inclusive or exclusive. If this argument is non-null, then it shall comply to the following conditions:

• The range shall be non-empty.
• value­Domain.get­Element­Type() shall be equal to one of the following:
  • to value­Class if the latter is not an array,
  • or to primitive­To­Wrapper(value­Class.get­Component­Type()) if value­Class is an array.

If both value­Domain and valid­Values are non-null, then all valid values shall be contained in the value domain.

Parameters:

properties - the properties to be given to the identified object.

minimum­Occurs - the minimum number of times that values for this parameter group are required, or 0 if no restriction.

maximum­Occurs - the maximum number of times that values for this parameter group are required, or Integer.MAX_VALUE if no restriction.

value­Class - the class that describes the type of the parameter value.

value­Domain - the minimum value, maximum value and unit of measurement, or null if none.

valid­Values - the list of valid values, or null if there is no restriction. This property is mostly for restricting values to a code list or enumeration subset. It is not necessary to provide this property when all values from the code list or enumeration are valid.

default­Value - the default value for the parameter, or null if none.

DefaultParameterDescriptor

protected DefaultParameterDescriptor(ParameterDescriptor<T> descriptor)

Creates a new descriptor with the same values than the specified one. This copy constructor provides a way to convert an arbitrary implementation into a SIS one or a user-defined one (as a subclass), usually in order to leverage some implementation-specific API.

This constructor performs a shallow copy, i.e. the properties are not cloned.

Parameters:

descriptor - the descriptor to shallow copy.

See Also:

• cast­Or­Copy(Parameter­Descriptor)

Method Details

castOrCopy

public static <T> DefaultParameterDescriptor<T> castOrCopy(ParameterDescriptor<T> object)

Returns a SIS parameter implementation with the same values than the given arbitrary implementation. If the given object is null, then this method returns null. Otherwise if the given object is already a SIS implementation, then the given object is returned unchanged. Otherwise a new SIS implementation is created and initialized to the values of the given object.

Type Parameters:

T - the type of values.

Parameters:

object - the object to get as a SIS implementation, or null if none.

Returns:

a SIS implementation containing the values of the given object (may be the given object itself), or null if the argument was null.

getInterface

public Class<? extends ParameterDescriptor<T>> getInterface()

Returns the GeoAPI interface implemented by this class. The SIS implementation returns Parameter­Descriptor.class.

Note for implementers

Subclasses usually do not need to override this method since GeoAPI does not define Parameter­Descriptor sub-interface. Overriding possibility is left mostly for implementers who wish to extend GeoAPI with their own set of interfaces.

Overrides:

get­Interface in class Abstract­Parameter­Descriptor

Returns:

Parameter­Descriptor.class or a user-defined sub-interface.

getValueType

public TypeName getValueType()

Returns the name that describes the type of parameter values. This is closely related to the Class returned by get­Value­Class():

• If the value class is a collection (e.g. List or array), then this method returns the type of elements in the collection.
• Otherwise this method returns the value class using the mapping documented in Default­Type­Name javadoc.

Type­Name is used for encoding parameters in XML or JSON documents, while get­Value­Class() is used for programmatic purposes.

Returns:

the type name of value component(s) in this parameter.

Since:

1.3

getValueClass

public final Class<T> getValueClass()

Returns the class that describes the type of parameter values.

Specified by:

get­Value­Class in interface Parameter­Descriptor<T>

Returns:

the parameter value class.

getValidValues

public Set<T> getValidValues()

If this parameter allows only a finite set of values, returns that set. The set of valid values is usually a code list or enumeration. This method returns null if this parameter does not limit values to a finite set.

Specified by:

get­Valid­Values in interface Parameter­Descriptor<T>

Returns:

a finite set of valid values (usually from a code list), or null if it does not apply or if there is no restriction.

getValueDomain

public final Range<?> getValueDomain()

Returns the domain of values with their unit of measurement (if any), or null if none. The Range object combines the value class, minimum value, maximum value and whether these values are inclusive or inclusive. If the range is an instance of Measurement­Range, then it also contains the unit of measurement.

API note

If this method returns a non-null value, then its type is either exactly Range<T>, or Range<E> where <E> is the component type of <T> (using wrapper classes for primitive types).

Returns:

the domain of values, or null.

See Also:

• Parameters.get­Value­Domain(Parameter­Descriptor)

getMinimumValue

public Comparable<T> getMinimumValue()

Returns the minimum parameter value. If there is no minimum value, or if minimum value is inappropriate for the value class, then this method returns null.

This is a convenience method for get­Value­Domain().get­Min­Value(). Note that this method said nothing about whether the value is inclusive.

Specified by:

get­Minimum­Value in interface Parameter­Descriptor<T>

Returns:

the minimum parameter value (often an instance of Double), or null if unbounded.

getMaximumValue

public Comparable<T> getMaximumValue()

Returns the maximum parameter value. If there is no maximum value, or if maximum value is inappropriate for the value type, then this method returns null.

This is a convenience method for get­Value­Domain().get­Max­Value(). Note that this method said nothing about whether the value is inclusive.

Specified by:

get­Maximum­Value in interface Parameter­Descriptor<T>

Returns:

the minimum parameter value (often an instance of Double), or null if unbounded.

getDefaultValue

public T getDefaultValue()

Returns the default value for the parameter. The return type can be any type including a Number or a String. If there is no default value, then this method returns null.

Specified by:

get­Default­Value in interface Parameter­Descriptor<T>

Returns:

the default value, or null in none.

getUnit

public Unit<?> getUnit()

Returns the unit of measurement for the minimum, maximum and default values. This attribute apply only if the values is of numeric type (usually an instance of Double).

This is a convenience method for get­Value­Domain().unit().

Specified by:

get­Unit in interface Parameter­Descriptor<T>

Returns:

the unit for numeric value, or null if it doesn't apply to the value type.

createValue

public ParameterValue<T> createValue()

Creates a new parameter value instance initialized with the default value. The parameter descriptor for the created parameter value will be this object.

Specified by:

create­Value in interface General­Parameter­Descriptor

Specified by:

create­Value in interface Parameter­Descriptor<T>

Returns:

a parameter initialized to the default value.

equals

public boolean equals(Object object,
 ComparisonMode mode)

Compares the specified object with this parameter for equality. The strictness level is controlled by the second argument. This method compares the following properties in every cases:

• Abstract­Identified­Object.get­Name(), compared heuristically in IGNORE_METADATA or less strict mode.
• get­Value­Class()
• get­Default­Value()
• get­Unit()

All other properties (minimum and maximum occurrences, minimum, maximum and valid values) are compared only for modes stricter than Comparison­Mode.IGNORE_METADATA.

Specified by:

equals in interface Lenient­Comparable

Overrides:

equals in class Abstract­Parameter­Descriptor

Parameters:

object - the object to compare to this.

mode - the strictness level of the comparison.

Returns:

true if both objects are equal according the given comparison mode.

See Also:

• Abstract­Identified­Object.compute­Hash­Code()
• Utilities.deep­Equals(Object, Object, Comparison­Mode)

computeHashCode

protected long computeHashCode()

Invoked by Abstract­Identified­Object.hash­Code() for computing the hash code when first needed.

Overrides:

compute­Hash­Code in class Abstract­Identified­Object

Returns:

the hash code value. This value may change in any future Apache SIS version.