com.vaadin.flow.data.provider.hierarchy

Class TreeData<T>

java.lang.Object

com.vaadin.flow.data.provider.hierarchy.TreeData<T>

Type Parameters:

T - data type

All Implemented Interfaces:

Serializable

public class TreeData<T>
extends Object
implements Serializable

Class for representing hierarchical data.

Typically used as a backing data source for TreeDataProvider.

Author:

Vaadin Ltd

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
TreeData() Creates an initially empty hierarchical data representation to which items can be added or removed.

Method Summary

Modifier and Type	Method and Description
TreeData<T>	addItem(T parent, T item) Adds a data item as a child of parent.
TreeData<T>	addItems(Collection<T> rootItems, ValueProvider<T,Collection<T>> childItemProvider) Adds the given items as root items and uses the given value provider to recursively populate children of the root items.
TreeData<T>	addItems(Stream<T> rootItems, ValueProvider<T,Stream<T>> childItemProvider) Adds the given items as root items and uses the given value provider to recursively populate children of the root items.
TreeData<T>	addItems(T parent, Collection<T> items) Adds a list of data items as children of parent.
TreeData<T>	addItems(T parent, Stream<T> items) Adds data items contained in a stream as children of parent.
TreeData<T>	addItems(T parent, T... items) Adds a list of data items as children of parent.
TreeData<T>	addRootItems(Collection<T> items) Adds the items of the given collection as root items to this structure.
TreeData<T>	addRootItems(Stream<T> items) Adds the items of the given stream as root items to this structure.
TreeData<T>	addRootItems(T... items) Adds the items as root items to this structure.
TreeData<T>	clear() Clear all items from this structure.
boolean	contains(T item) Check whether the given item is in this hierarchy.
List<T>	getChildren(T item) Get the immediate child items for the given item.
T	getParent(T item) Get the parent item for the given item.
List<T>	getRootItems() Gets the root items of this structure.
void	moveAfterSibling(T item, T sibling) Moves an item to the position immediately after a sibling item.
TreeData<T>	removeItem(T item) Remove a given item from this structure.
void	setParent(T item, T parent) Moves an item to become a child of the given parent item.

Methods inherited from class java.lang.Object

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

Constructor Detail

TreeData

public TreeData()

Creates an initially empty hierarchical data representation to which items can be added or removed.

Method Detail

addRootItems

public TreeData<T> addRootItems(T... items)

Adds the items as root items to this structure.

Parameters:

items - the items to add

Returns:

this

Throws:

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are {code null}

addRootItems

public TreeData<T> addRootItems(Collection<T> items)

Adds the items of the given collection as root items to this structure.

Parameters:

items - the collection of items to add

Returns:

this

Throws:

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are {code null}

addRootItems

public TreeData<T> addRootItems(Stream<T> items)

Adds the items of the given stream as root items to this structure.

Parameters:

items - the stream of root items to add

Returns:

this

Throws:

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are {code null}

addItem

public TreeData<T> addItem(T parent,
                           T item)

Adds a data item as a child of parent. Call with null as parent to add a root level item. The given parent item must already exist in this structure, and an item can only be added to this structure once.

Parameters:

parent - the parent item for which the items are added as children

item - the item to add

Returns:

this

Throws:

IllegalArgumentException - if parent is not null and not already added to this structure

IllegalArgumentException - if the item has already been added to this structure

NullPointerException - if item is null

addItems

public TreeData<T> addItems(T parent,
                            T... items)

Adds a list of data items as children of parent. Call with null as parent to add root level items. The given parent item must already exist in this structure, and an item can only be added to this structure once.

Parameters:

parent - the parent item for which the items are added as children

items - the list of items to add

Returns:

this

Throws:

IllegalArgumentException - if parent is not null and not already added to this structure

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are null

addItems

public TreeData<T> addItems(T parent,
                            Collection<T> items)

Adds a list of data items as children of parent. Call with null as parent to add root level items. The given parent item must already exist in this structure, and an item can only be added to this structure once.

Parameters:

parent - the parent item for which the items are added as children

items - the collection of items to add

Returns:

this

Throws:

IllegalArgumentException - if parent is not null and not already added to this structure

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are null

addItems

public TreeData<T> addItems(T parent,
                            Stream<T> items)

Adds data items contained in a stream as children of parent. Call with null as parent to add root level items. The given parent item must already exist in this structure, and an item can only be added to this structure once.

Parameters:

parent - the parent item for which the items are added as children

items - stream of items to add

Returns:

this

Throws:

IllegalArgumentException - if parent is not null and not already added to this structure

IllegalArgumentException - if any of the given items have already been added to this structure

NullPointerException - if any of the items are null

addItems

public TreeData<T> addItems(Collection<T> rootItems,
                            ValueProvider<T,Collection<T>> childItemProvider)

Adds the given items as root items and uses the given value provider to recursively populate children of the root items.

Parameters:

rootItems - the root items to add

childItemProvider - the value provider used to recursively populate this TreeData from the given root items

Returns:

this

addItems

public TreeData<T> addItems(Stream<T> rootItems,
                            ValueProvider<T,Stream<T>> childItemProvider)

Adds the given items as root items and uses the given value provider to recursively populate children of the root items.

Parameters:

rootItems - the root items to add

childItemProvider - the value provider used to recursively populate this TreeData from the given root items

Returns:

this

removeItem

public TreeData<T> removeItem(T item)

Remove a given item from this structure. Additionally, this will recursively remove any descendants of the item.

Parameters:

item - the item to remove, or null to clear all data

Returns:

this

Throws:

IllegalArgumentException - if the item does not exist in this structure

clear

public TreeData<T> clear()

Clear all items from this structure. Shorthand for calling removeItem(Object) with null.

Returns:

this

getRootItems

public List<T> getRootItems()

Gets the root items of this structure.

Returns:

an unmodifiable list of root items of this structure

getChildren

public List<T> getChildren(T item)

Get the immediate child items for the given item.

Parameters:

item - the item for which to retrieve child items for, null to retrieve all root items

Returns:

an unmodifiable list of child items for the given item

Throws:

IllegalArgumentException - if the item does not exist in this structure

getParent

public T getParent(T item)

Get the parent item for the given item.

Parameters:

item - the item for which to retrieve the parent item for

Returns:

parent item for the given item or null if the item is a root item.

Throws:

IllegalArgumentException - if the item does not exist in this structure

setParent

public void setParent(T item,
                      T parent)

Moves an item to become a child of the given parent item. The new parent item must exist in the hierarchy. Setting the parent to null makes the item a root item. After making changes to the tree data, AbstractDataProvider.refreshAll() should be called.

Parameters:

item - the item to be set as the child of parent

parent - the item to be set as parent or null to set the item as root

moveAfterSibling

public void moveAfterSibling(T item,
                             T sibling)

Moves an item to the position immediately after a sibling item. The two items must have the same parent. After making changes to the tree data, AbstractDataProvider.refreshAll() should be called.

Parameters:

item - the item to be moved

sibling - the item after which the moved item will be located, or null to move item to first position

contains

public boolean contains(T item)

Check whether the given item is in this hierarchy.

Parameters:

item - the item to check

Returns:

true if the item is in this hierarchy, false if not