org.spongepowered.api.data.value

Interface BaseValue<E>

Type Parameters:

E - The type of element wrapped by this value

All Known Subinterfaces:

BoundedValue<E>, CollectionValue<E,C,V,I>, ImmutableBoundedValue<E>, ImmutableCollectionValue<E,C,I,M>, ImmutableListValue<E>, ImmutableMapValue<K,V>, ImmutableOptionalValue<E>, ImmutablePatternListValue, ImmutableSetValue<E>, ImmutableValue<E>, ImmutableWeightedCollectionValue<E>, ListValue<E>, MapValue<K,V>, MutableBoundedValue<E>, OptionalValue<E>, PatternListValue, SetValue<E>, Value<E>, WeightedCollectionValue<E>

public interface BaseValue<E>

The abstract base interface for all of the "Value API". In short, a BaseValue is a "wrapper" around an actual value from a ValueContainer. The actual value may come from various sources of the ValueContainer, but usually it's a generic dynamic system for being able to fetch values from object fields without having to know the type of Class of the ValueContainer, the getters and setters for that particular value. The driving force behind this is that instead of having a traditional hierarchical structure of data that is possible to be retrieved from an Entity, Living, etc., all that is required is

 container.supports(Keys.HEALTH) ?
 container.get(Keys.HEALTH).get() : 0 

where the container is simply a ValueContainer, nothing more, nothing less.

The advantage of this is that now, these various known and unknown Values can be retrieved by simple java generics: ValueContainer.getValue(Key). While having a Value for something so primitive as the current health of a Living entity, the power is wielded when a Value can be offered up to multiple ValueContainers without worrying about whether it's supported or not, or getting the right cast information.

Method Summary

Modifier and Type	Method and Description
boolean	exists() Checks that the underlying value exists (or "set").
E	get() Gets the held value.
E	getDefault() Gets the default value.
Optional<E>	getDirect() Gets the direct value.
Key<? extends BaseValue<E>>	getKey() Gets the key for this BaseValue.

Method Detail

get

E get()

Gets the held value. Usually all held values are "filled" and not "defaulted"; however, in the case that the actual value is not set or exists() returns false, the getDefault() value is returned.

Returns:

The held value

exists

boolean exists()

Checks that the underlying value exists (or "set").

Returns:

True if the value exists or was set

getDefault

E getDefault()

Gets the default value. There is always a default value, however, usability of the default value may be questionable in certain circumstances.

Returns:

The default value

getDirect

Optional<E> getDirect()

Gets the direct value. Since some values may be absent for various reasons, the get() would return the getDefault() when necessary.

Returns:

The direct value, if available

getKey

Key<? extends BaseValue<E>> getKey()

Gets the key for this BaseValue.

Returns:

The key for this value