Package org.elasticsearch.common.settings

Interface AbstractScopedSettings.SettingUpdater<T>

Type Parameters:

T - the type of the value of the setting

Enclosing class:

AbstractScopedSettings

public static interface AbstractScopedSettings.SettingUpdater<T>

Transactional interface to update settings.

See Also:

Setting

Method Summary

Modifier and Type	Method	Description
default boolean	apply(Settings current, Settings previous)	Updates this updaters value if it has changed.
void	apply(T value, Settings current, Settings previous)	Applies the given value to the updater.
T	getValue(Settings current, Settings previous)	Returns the instance value for the current settings.
boolean	hasChanged(Settings current, Settings previous)	Returns true if this updaters setting has changed with the current update
default Runnable	updater(Settings current, Settings previous)	Returns a callable runnable that calls apply(Object, Settings, Settings) if the settings actually changed.

Method Details

hasChanged

boolean hasChanged(Settings current,
 Settings previous)

Returns true if this updaters setting has changed with the current update

Parameters:

current - the current settings

previous - the previous setting

Returns:

true if this updaters setting has changed with the current update

getValue

T getValue(Settings current,
 Settings previous)

Returns the instance value for the current settings. This method is stateless and idempotent. This method will throw an exception if the source of this value is invalid.

apply

void apply(T value,
 Settings current,
 Settings previous)

Applies the given value to the updater. This methods will actually run the update.

apply

default boolean apply(Settings current,
 Settings previous)

Updates this updaters value if it has changed.

Returns:

true iff the value has been updated.

updater

default Runnable updater(Settings current,
 Settings previous)

Returns a callable runnable that calls apply(Object, Settings, Settings) if the settings actually changed. This allows to defer the update to a later point in time while keeping type safety. If the value didn't change the returned runnable is a noop.