Module xaos.ui

Package eu.ess.xaos.ui.control.tree

Class TreeItemWalker<T>

java.lang.Object

eu.ess.xaos.ui.control.tree.TreeItemWalker<T>

Type Parameters:

T - The type of the TreeItems.

All Implemented Interfaces:

Iterable<TreeItem<T>>, Iterator<TreeItem<T>>

public class TreeItemWalker<T>
extends Object
implements Iterator<TreeItem<T>>, Iterable<TreeItem<T>>

Walks a TreeItems tree depth-first. It supports streaming, visitor pattern and iterator pattern.

Important Note #1: Once used, a TreeItemWalker cannot be reused. A new instance has to be created instead.

Important Note #2: TreeItems added to the tree being walked will be walked only if they are part of the sub-tree not yet visited. Generally speaking no changes should be done to the tree structure during a walk.

Important Note #3: This implementation is not synchronized. Calling getDepth(), hasNext(), next() and/or stream()'s methods from different threads concurrently can produce odd results. Call buildSynchronized to get a synchronized version of the walker.

Author:

claudio.rosati@esss.se

See Also:

Iterate TreeView nodes

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	TreeItemWalker(TreeItem<T> root)	Initialize the walker with the given root item.
protected	TreeItemWalker(TreeTableView<T> view)	Initialize the walker with the TreeTableView.getRoot() from the given view.
protected	TreeItemWalker(TreeView<T> view)	Initialize the walker with the TreeView.getRoot() from the given view.

Method Summary

Modifier and Type	Method	Description
static <T> TreeItemWalker<T>	build(TreeItem<T> root)	Returns a walker initialized with the given root item.
static <T> TreeItemWalker<T>	build(TreeTableView<T> view)	Returns a walker initialized with the TreeTableView.getRoot() from the given view.
static <T> TreeItemWalker<T>	build(TreeView<T> view)	Returns a walker initialized with the TreeView.getRoot() from the given view.
static <T> TreeItemWalker<T>	buildSynchronized(TreeItem<T> root)	Returns a synchronized walker initialized with the given root item.
static <T> TreeItemWalker<T>	buildSynchronized(TreeTableView<T> view)	Returns a synchronized walker initialized with the TreeTableView.getRoot() from the given view.
static <T> TreeItemWalker<T>	buildSynchronized(TreeView<T> view)	Returns a synchronized walker initialized with the TreeView.getRoot() from the given view.
protected Stream<TreeItem<T>>	createStream()
int	getDepth()
boolean	hasNext()
Iterator<TreeItem<T>>	iterator()
TreeItem<T>	next()
Spliterator<TreeItem<T>>	spliterator()
Stream<TreeItem<T>>	stream()
static <T> void	visit(TreeItem<T> root, BiConsumer<TreeItem<T>,Integer> visitor)	Walks over the given tree root and calls the consumer for each tree item.
static <T> void	visit(TreeItem<T> root, Consumer<TreeItem<T>> visitor)	Walks over the given tree root and calls the consumer for each tree item.
static <T> void	visit(TreeTableView<T> tree, BiConsumer<TreeItem<T>,Integer> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item.
static <T> void	visit(TreeTableView<T> tree, Consumer<TreeItem<T>> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item.
static <T> void	visit(TreeView<T> tree, BiConsumer<TreeItem<T>,Integer> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item.
static <T> void	visit(TreeView<T> tree, Consumer<TreeItem<T>> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item.
static <T> void	visitValue(TreeItem<T> root, BiConsumer<T,Integer> visitor)	Walks over the given tree root and calls the consumer for each tree item's value.
static <T> void	visitValue(TreeItem<T> root, Consumer<T> visitor)	Walks over the given tree root and calls the consumer for each tree item's value.
static <T> void	visitValue(TreeTableView<T> tree, BiConsumer<T,Integer> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item's value.
static <T> void	visitValue(TreeTableView<T> tree, Consumer<T> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item's value.
static <T> void	visitValue(TreeView<T> tree, BiConsumer<T,Integer> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item's value.
static <T> void	visitValue(TreeView<T> tree, Consumer<T> visitor)	Walks over the given root of the given tree and calls the consumer for each tree item's value.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach

Methods inherited from interface java.util.Iterator

forEachRemaining, remove

Constructor Detail

TreeItemWalker

protected TreeItemWalker(TreeItem<T> root)

Initialize the walker with the given root item.

Parameters:

root - The TreeItem being the root to be walked depth-first. Can be null, in which case an empty walker will be created.

TreeItemWalker

protected TreeItemWalker(TreeView<T> view)

Initialize the walker with the TreeView.getRoot() from the given view.

Parameters:

view - The TreeView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

TreeItemWalker

protected TreeItemWalker(TreeTableView<T> view)

Initialize the walker with the TreeTableView.getRoot() from the given view.

Parameters:

view - The TreeTableView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

Method Detail

build

public static <T> TreeItemWalker<T> build(TreeItem<T> root)

Returns a walker initialized with the given root item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The TreeItem being the root to be walked depth-first. Can be null, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given root parameter.

build

public static <T> TreeItemWalker<T> build(TreeView<T> view)

Returns a walker initialized with the TreeView.getRoot() from the given view.

Type Parameters:

T - The type of the TreeItems.

Parameters:

view - The TreeView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given view parameter.

build

public static <T> TreeItemWalker<T> build(TreeTableView<T> view)

Returns a walker initialized with the TreeTableView.getRoot() from the given view.

Type Parameters:

T - The type of the TreeItems.

Parameters:

view - The TreeTableView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given view parameter.

buildSynchronized

public static <T> TreeItemWalker<T> buildSynchronized(TreeItem<T> root)

Returns a synchronized walker initialized with the given root item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The TreeItem being the root to be walked depth-first. Can be null, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given root parameter.

buildSynchronized

public static <T> TreeItemWalker<T> buildSynchronized(TreeView<T> view)

Returns a synchronized walker initialized with the TreeView.getRoot() from the given view.

Type Parameters:

T - The type of the TreeItems.

Parameters:

view - The TreeView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given view parameter.

buildSynchronized

public static <T> TreeItemWalker<T> buildSynchronized(TreeTableView<T> view)

Returns a synchronized walker initialized with the TreeTableView.getRoot() from the given view.

Type Parameters:

T - The type of the TreeItems.

Parameters:

view - The TreeTableView whose root element has to be walked depth-first. Can be null, or having a null root element, in which case an empty walker will be created.

Returns:

A new instance of TreeItemWalker initialized with the given view parameter.

visit

public static <T> void visit(TreeItem<T> root,
                             Consumer<TreeItem<T>> visitor)

Walks over the given tree root and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The root TreeItem to visit.

visitor - The visitor receiving the visited TreeItem during the tree walk.

visit

public static <T> void visit(TreeItem<T> root,
                             BiConsumer<TreeItem<T>,Integer> visitor)

Walks over the given tree root and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The root TreeItem to visit.

visitor - The visitor receiving the visited TreeItem and the current walking depth during the tree walk.

visit

public static <T> void visit(TreeView<T> tree,
                             Consumer<TreeItem<T>> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem during the tree walk.

visit

public static <T> void visit(TreeView<T> tree,
                             BiConsumer<TreeItem<T>,Integer> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem and the current walking depth during the tree walk.

visit

public static <T> void visit(TreeTableView<T> tree,
                             Consumer<TreeItem<T>> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeTableView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem during the tree walk.

visit

public static <T> void visit(TreeTableView<T> tree,
                             BiConsumer<TreeItem<T>,Integer> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeTableView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem and the current walking depth during the tree walk.

visitValue

public static <T> void visitValue(TreeItem<T> root,
                                  Consumer<T> visitor)

Walks over the given tree root and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The root TreeItem to visit.

visitor - The visitor receiving the visited TreeItem's value during the tree walk.

visitValue

public static <T> void visitValue(TreeItem<T> root,
                                  BiConsumer<T,Integer> visitor)

Walks over the given tree root and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

root - The root TreeItem to visit.

visitor - The visitor receiving the visited TreeItem's value and the current walking depth during the tree walk.

visitValue

public static <T> void visitValue(TreeView<T> tree,
                                  Consumer<T> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem's value during the tree walk.

visitValue

public static <T> void visitValue(TreeView<T> tree,
                                  BiConsumer<T,Integer> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem's value and the current walking depth during the tree walk.

visitValue

public static <T> void visitValue(TreeTableView<T> tree,
                                  Consumer<T> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeTableView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem's value during the tree walk.

visitValue

public static <T> void visitValue(TreeTableView<T> tree,
                                  BiConsumer<T,Integer> visitor)

Walks over the given root of the given tree and calls the consumer for each tree item's value.

Type Parameters:

T - The type of the TreeItems.

Parameters:

tree - The TreeTableView whose root has to be visited.

visitor - The visitor receiving the visited TreeItem's value and the current walking depth during the tree walk.

getDepth

public int getDepth()

Returns:

The current depth level. 0 means "root item" (the one used to build this walker). 1 means "root's child" and so on.

hasNext

public boolean hasNext()

Specified by:

hasNext in interface Iterator<T>

Returns:

true if the walker still has unserved items.

iterator

public Iterator<TreeItem<T>> iterator()

Specified by:

iterator in interface Iterable<T>

next

public TreeItem<T> next()

Specified by:

next in interface Iterator<T>

Returns:

The next tree item in depth-first walk order: the parent is returned before any of its children.

spliterator

public Spliterator<TreeItem<T>> spliterator()

Specified by:

spliterator in interface Iterable<T>

stream

public Stream<TreeItem<T>> stream()

Returns:

A Stream of all (remaining) items. Note that the walker can traverse only once over items. So if hasNext()/next() where used to partially walk the tree, a following call to stream() will return the remaining items.

createStream

protected Stream<TreeItem<T>> createStream()