net.sf.mmm.util.lang.api

Interface EnumDefinition<TYPE,CATEGORY>

Type Parameters:

TYPE - is the generic type of the enum type.

CATEGORY - is the generic type of the category or Void for none.

All Superinterfaces:

AttributeReadValue<String>, Datatype, Serializable, SimpleDatatype<String>

All Known Implementing Classes:

AbstractEnumDefinition, AbstractSimpleEnumDefinition, BooleanEnumDefinition, EnumEnumDefinition

public interface EnumDefinition<TYPE,CATEGORY>
extends SimpleDatatype<String>

This is the interface for the definition of an EnumType.
As an example we can think of an instance of this interface called country defined as EnumDefinition<Iso2CountryCode, Void>. This defines an enumeration based on the type Iso2CountryCode that has no category. Next, we define another instance of this interface called state defined as EnumDefinition <StateDatatype, Iso2CountryCode>. The method getCategory() will return the country instance we defined earlier. This means that a state is classified by a county.
ATTENTION:
The value is used as identifier key and has to be unique.

Since:

3.0.0

Author:

Joerg Hohwiller (hohwille at users.sourceforge.net)

Method Summary

Modifier and Type	Method and Description
EnumDefinition<CATEGORY,?>	getCategory()
Class<TYPE>	getEnumType()
Formatter<TYPE>	getFormatter() This method gets the Formatter used to format instances of the enum as String for end-users.
String	getValue() This method returns the raw value of this datatype.
boolean	isCachable()
boolean	isMutable()

Methods inherited from interface net.sf.mmm.util.lang.api.Datatype

toString

Method Detail

getCategory

EnumDefinition<CATEGORY,?> getCategory()

Returns:

the EnumDefinition this EnumDefinition is categorized by or null for no category (then <CATEGORY> shall be bound to Void).

getFormatter

Formatter<TYPE> getFormatter()

This method gets the Formatter used to format instances of the enum as String for end-users. By default FormatterToString can be used. However, e.g. for the type Boolean you might want to display as "yes" or "no" and might have an alternative EnumDefinition for Boolean that displays as "all" or "none". Further, also I18N (see NlsMessage) can be addressed by this Formatter. ATTENTION:
A EnumDefinition may be used with or without allowing a null value. Therefore, this Formatter should be able to properly format null (see AbstractFormatter#formatNull()). E.g. a Boolean option in a search form may be optional and displayed as "any".

Returns:

the Formatter.

getEnumType

Class<TYPE> getEnumType()

Returns:

the EnumType of this EnumDefinition.

isMutable

boolean isMutable()

Returns:

true if EnumType-instances of this type can be added or removed, false otherwise (e.g. if implemented by a Enum).

isCachable

boolean isCachable()

Returns:

true if all EnumType-instances of this type can cached (default) or false if there are too many of them (e.g. for entities like cities of the world).

getValue

String getValue()

This method returns the raw value of this datatype. This will typically be a standard datatype (like String, Character, Boolean, any type of Number, any type of java.time.LocalDate, etc.).
ATTENTION:
The value is used as identifier for this enum type and has to be unique for all available enumerations.

Specified by:

getValue in interface AttributeReadValue<String>

Specified by:

getValue in interface SimpleDatatype<String>

Returns:

the value of this datatype.