com.vaadin.data.provider

Class HierarchyMapper<T,F>

java.lang.Object

com.vaadin.data.provider.HierarchyMapper<T,F>

Type Parameters:

T - the data type

F - the filter type

All Implemented Interfaces:

DataGenerator<T>, Serializable

public class HierarchyMapper<T,F>
extends Object
implements DataGenerator<T>

Mapper for hierarchical data.

Keeps track of the expanded nodes, and size of of the subtrees for each expanded node.

This class is framework internal implementation details, and can be changed / moved at any point. This means that you should not directly use this for anything.

Since:

8.1

Author:

Vaadin Ltd

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
HierarchyMapper(HierarchicalDataProvider<T,F> provider) Constructs a new HierarchyMapper.

Method Summary

Modifier and Type	Method and Description
Range	collapse(T item, Integer position) Collapses the given item.
void	destroyAllData() Informs the DataGenerator that all data has been dropped.
Range	doCollapse(T item, Optional<Integer> position) Deprecated. Use collapse(Object, Integer) instead.
Range	doExpand(T item, Optional<Integer> position) Deprecated. Use expand(Object, Integer) instead.
Range	expand(T item, Integer position) Expands the given item.
Stream<T>	fetchItems(Range range) Gets a stream of items in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.
Stream<T>	fetchItems(T parent, Range range) Gets a stream of children for the given item in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.
void	generateData(T item, JsonObject jsonObject) Adds custom data for the given item to its serialized JsonObject representation.
List<QuerySortOrder>	getBackEndSorting() Gets the current back-end sorting.
HierarchicalDataProvider<T,F>	getDataProvider() Gets the HierarchicalDataProvider for this HierarchyMapper.
F	getFilter() Gets the current filter.
Optional<Integer>	getIndexOf(T target) Finds the current index of given object.
Comparator<T>	getInMemorySorting() Gets the current in-memory sorting.
ItemCollapseAllowedProvider<T>	getItemCollapseAllowedProvider() Gets the current item collapse allowed provider.
Integer	getParentIndex(T item) Finds the index of the parent of the item in given target index.
protected T	getParentOfItem(T item) Find parent for the given item among open folders.
int	getTreeSize() Returns the size of the currently expanded hierarchy.
boolean	hasChildren(T item) Returns whether given item has children.
boolean	isExpanded(T item) Returns whether the given item is expanded.
protected void	registerChildren(T parent, List<T> childList) Register parent and children items into inner structures.
protected void	removeChildren(Object id) Removes all children of an item identified by a given id.
void	setBackEndSorting(List<QuerySortOrder> backEndSorting) Sets the current back-end sorting.
void	setFilter(Object filter) Sets the current filter.
void	setInMemorySorting(Comparator<T> inMemorySorting) Sets the current in-memory sorting.
void	setItemCollapseAllowedProvider(ItemCollapseAllowedProvider<T> itemCollapseAllowedProvider) Sets the current item collapse allowed provider.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.vaadin.data.provider.DataGenerator

destroyData, refreshData

Constructor Detail

HierarchyMapper

public HierarchyMapper(HierarchicalDataProvider<T,F> provider)

Constructs a new HierarchyMapper.

Parameters:

provider - the hierarchical data provider for this mapper

Method Detail

getTreeSize

public int getTreeSize()

Returns the size of the currently expanded hierarchy.

Returns:

the amount of available data

getParentIndex

public Integer getParentIndex(T item)

Finds the index of the parent of the item in given target index.

Parameters:

item - the item to get the parent of

Returns:

the parent index or a negative value if the parent is not found

isExpanded

public boolean isExpanded(T item)

Returns whether the given item is expanded.

Parameters:

item - the item to test

Returns:

true if item is expanded; false if not

expand

public Range expand(T item,
                    Integer position)

Expands the given item.

Parameters:

item - the item to expand

position - the index of the item

Returns:

range of rows added by expanding the item

doExpand

@Deprecated
public Range doExpand(T item,
                                  Optional<Integer> position)

Deprecated. Use expand(Object, Integer) instead.

Expands the given item.

Parameters:

item - the item to expand

position - the index of item

Returns:

range of rows added by expanding the item

collapse

public Range collapse(T item,
                      Integer position)

Collapses the given item.

Parameters:

item - the item to collapse

position - the index of the item

Returns:

range of rows removed by collapsing the item

doCollapse

@Deprecated
public Range doCollapse(T item,
                                    Optional<Integer> position)

Deprecated. Use collapse(Object, Integer) instead.

Collapses the given item.

Parameters:

item - the item to collapse

position - the index of item

Returns:

range of rows removed by collapsing the item

generateData

public void generateData(T item,
                         JsonObject jsonObject)

Description copied from interface: DataGenerator

Adds custom data for the given item to its serialized JsonObject representation. This JSON object will be sent to client-side DataProvider.

Specified by:

generateData in interface DataGenerator<T>

Parameters:

item - the data item being serialized

jsonObject - the JSON object being sent to the client

getItemCollapseAllowedProvider

public ItemCollapseAllowedProvider<T> getItemCollapseAllowedProvider()

Gets the current item collapse allowed provider.

Returns:

the item collapse allowed provider

setItemCollapseAllowedProvider

public void setItemCollapseAllowedProvider(ItemCollapseAllowedProvider<T> itemCollapseAllowedProvider)

Sets the current item collapse allowed provider.

Parameters:

itemCollapseAllowedProvider - the item collapse allowed provider

getInMemorySorting

public Comparator<T> getInMemorySorting()

Gets the current in-memory sorting.

Returns:

the in-memory sorting

setInMemorySorting

public void setInMemorySorting(Comparator<T> inMemorySorting)

Sets the current in-memory sorting. This will cause the hierarchy to be constructed again.

Parameters:

inMemorySorting - the in-memory sorting

getBackEndSorting

public List<QuerySortOrder> getBackEndSorting()

Gets the current back-end sorting.

Returns:

the back-end sorting

setBackEndSorting

public void setBackEndSorting(List<QuerySortOrder> backEndSorting)

Sets the current back-end sorting. This will cause the hierarchy to be constructed again.

Parameters:

backEndSorting - the back-end sorting

getFilter

public F getFilter()

Gets the current filter.

Returns:

the filter

setFilter

public void setFilter(Object filter)

Sets the current filter. This will cause the hierarchy to be constructed again.

Parameters:

filter - the filter

getDataProvider

public HierarchicalDataProvider<T,F> getDataProvider()

Gets the HierarchicalDataProvider for this HierarchyMapper.

Returns:

the hierarchical data provider

hasChildren

public boolean hasChildren(T item)

Returns whether given item has children.

Parameters:

item - the node to test

Returns:

true if node has children; false if not

fetchItems

public Stream<T> fetchItems(Range range)

Gets a stream of items in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.

Parameters:

range - the requested item range

Returns:

the stream of items

fetchItems

public Stream<T> fetchItems(T parent,
                            Range range)

Gets a stream of children for the given item in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.

Parameters:

parent - the parent item for the fetch

range - the requested item range

Returns:

the stream of items

getParentOfItem

protected T getParentOfItem(T item)

Find parent for the given item among open folders.

Parameters:

item - the item

Returns:

parent item or null for root items or if the parent is closed

removeChildren

protected void removeChildren(Object id)

Removes all children of an item identified by a given id. Items removed by this method as well as the original item are all marked to be collapsed. May be overridden in subclasses for removing obsolete data to avoid memory leaks.

Parameters:

id - the item id

getIndexOf

public Optional<Integer> getIndexOf(T target)

Finds the current index of given object. This is based on a search in flattened version of the hierarchy.

Parameters:

target - the target object to find

Returns:

optional index of given object

registerChildren

protected void registerChildren(T parent,
                                List<T> childList)

Register parent and children items into inner structures. May be overridden in subclasses.

Parameters:

parent - the parent item

childList - list of parents children to be registered.

destroyAllData

public void destroyAllData()

Description copied from interface: DataGenerator

Informs the DataGenerator that all data has been dropped. This method should clean up any unneeded information stored for items.

Specified by:

destroyAllData in interface DataGenerator<T>