com.vaadin.flow.data.provider

Interface DataKeyMapper<T>

Type Parameters:

T - data type

All Superinterfaces:

Serializable

All Known Implementing Classes:

KeyMapper

public interface DataKeyMapper<T>
extends Serializable

DataKeyMapper to map data objects to key strings.

Since:

1.0

Method Summary

Modifier and Type	Method and Description
T	get(String key) Gets the data object identified by given key.
boolean	has(T dataObject) Check whether this key mapper contains the given data object.
String	key(T dataObject) Gets the key for data object.
void	refresh(T dataObject) Updates any existing mappings of given data object.
void	remove(T dataObject) Removes a data object from the key mapping.
void	removeAll() Removes all data objects from the key mapping.
void	setIdentifierGetter(ValueProvider<T,Object> identifierGetter) Takes identifier getter into use and updates existing mappings

Method Detail

key

String key(T dataObject)

Gets the key for data object. If no key exists beforehand, a new key is created.

Parameters:

dataObject - data object for key mapping

Returns:

key for given data object

has

boolean has(T dataObject)

Check whether this key mapper contains the given data object.

Parameters:

dataObject - the data object to check

Returns:

true if the given data object is contained in this key mapper, false otherwise

get

T get(String key)

Gets the data object identified by given key.

Parameters:

key - key of a data object

Returns:

identified data object; null if invalid key

remove

void remove(T dataObject)

Removes a data object from the key mapping. The key is also dropped. Dropped keys are not reused.

Parameters:

dataObject - dropped data object

removeAll

void removeAll()

Removes all data objects from the key mapping. The keys are also dropped. Dropped keys are not reused.

refresh

void refresh(T dataObject)

Updates any existing mappings of given data object. The equality of two data objects is determined by the equality of their identifiers provided by the given value provider.

Parameters:

dataObject - the data object to update

setIdentifierGetter

void setIdentifierGetter(ValueProvider<T,Object> identifierGetter)

Takes identifier getter into use and updates existing mappings

Parameters:

identifierGetter - has to return a unique key for every bean, and the returned key has to follow general hashCode() and equals() contract, see Object.hashCode() for details.