Package de.xima.fc.common.tree

Class TreeParentIterable<Node,Id>

java.lang.Object

de.xima.fc.common.tree.TreeParentIterable<Node,Id>

Type Parameters:

Node - Type of the items in the tree.

Id - Type of the identifier that identifiers the items in the tree.

All Implemented Interfaces:

Iterable<Node>

public final class TreeParentIterable<Node,Id>
extends Object
implements Iterable<Node>

An iterable that iterates over a tree-like graph, starting at a given node, and accessing each parent. Throws an exception in case the graph is not a tree, thus also preventing endless cycles when the graph is cyclic.

Since:

8.2.0

Author:

XIMA MEDIA GmbH

Constructor Summary

Constructors

Constructor	Description
TreeParentIterable(Node startItem, boolean includeStartItem, ITreeParentAccessor<Node,Id> treeAccessor)	Returns a new iterable over the parents in the tree, starting at the given item.
TreeParentIterable(Node startItem, ITreeParentAccessor<Node,Id> treeAccessor)	Returns a new iterable over the parents in the tree, starting at the given item.

Method Summary

Modifier and Type	Method	Description
static <Node> Node	closestParentExcludingStart(Node startItem, ITreeParentAccessor<Node,?> treeAccessor, Predicate<? super Node> filter)	Finds the closest parent of the given item that matches the given filter.
static <Node> Node	closestParentIncludingStart(Node startItem, ITreeParentAccessor<Node,?> treeAccessor, Predicate<? super Node> filter)	Finds the closest parent of the given item that matches the given filter.
Iterator<Node>	iterator()
static <Node> List<Node>	toList(Node startItem, boolean includeStartItem, ITreeParentAccessor<Node,?> treeAccessor)	Iterates over the node and its parents, and returns a list of all iterated nodes.
static <Node> Set<Node>	toSet(Node startItem, boolean includeStartItem, ITreeParentAccessor<Node,?> treeAccessor)	Iterates over the node and its parents, and returns a set of all iterated nodes.

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, spliterator

Constructor Detail

TreeParentIterable

public TreeParentIterable(Node startItem,
                          boolean includeStartItem,
                          ITreeParentAccessor<Node,Id> treeAccessor)

Returns a new iterable over the parents in the tree, starting at the given item.

Parameters:

startItem - Child item where to start the traversal.

includeStartItem - Whether to include the start item in the iteration.

treeAccessor - Handler for accessing the parent of a node and its ID.

TreeParentIterable

public TreeParentIterable(Node startItem,
                          ITreeParentAccessor<Node,Id> treeAccessor)

Returns a new iterable over the parents in the tree, starting at the given item.

Parameters:

startItem - Child item where to start the traversal. This item is inluded in the traversal.

treeAccessor - Handler for accessing the parent of a node and its ID.

Method Detail

iterator

public Iterator<Node> iterator()

Specified by:

iterator in interface Iterable<Node>

closestParentExcludingStart

public static <Node> Node closestParentExcludingStart(Node startItem,
                                                      ITreeParentAccessor<Node,?> treeAccessor,
                                                      Predicate<? super Node> filter)

Finds the closest parent of the given item that matches the given filter. Does not include the start node in the list of candidates. A null filter is treated as no filter, i.e. so this method returns the first parent.

Type Parameters:

Node - Type of the items in the tree.

Parameters:

startItem - Node where to start the traversal.

treeAccessor - Handler for accessing the parent of a node, and its identifier.

filter - Predicate to filter the nodes.

Returns:

The closest parent of the given item that matches the given filter. null if no such parent exists.

closestParentIncludingStart

public static <Node> Node closestParentIncludingStart(Node startItem,
                                                      ITreeParentAccessor<Node,?> treeAccessor,
                                                      Predicate<? super Node> filter)

Finds the closest parent of the given item that matches the given filter. Include the start node in the list of candidates. A null filter is treated as no filter, i.e. this method returns the start node itself.

Type Parameters:

Node - Type of the items in the tree.

Parameters:

startItem - Node where to start the traversal.

treeAccessor - Handler for accessing the parent of a node, and its identifier.

filter - Predicate to filter the nodes.

Returns:

The closest parent of the given item that matches the given filter. null if no such parent exists.

toList

public static <Node> List<Node> toList(Node startItem,
                                       boolean includeStartItem,
                                       ITreeParentAccessor<Node,?> treeAccessor)

Iterates over the node and its parents, and returns a list of all iterated nodes.

Type Parameters:

Node - Type of the items in the tree.

Parameters:

startItem - Node where to start the traversal. This item is included in the returned list.

includeStartItem - Whether to include the start item in the iteration.

treeAccessor - Handler for accessing the parent of a node, and its identifier.

Returns:

A list with the given start item and all its parents.

toSet

public static <Node> Set<Node> toSet(Node startItem,
                                     boolean includeStartItem,
                                     ITreeParentAccessor<Node,?> treeAccessor)

Iterates over the node and its parents, and returns a set of all iterated nodes.

Type Parameters:

Node - Type of the items in the tree.

Parameters:

startItem - Node where to start the traversal. This item is included in the returned list.

includeStartItem - Whether to include the start item in the iteration.

treeAccessor - Handler for accessing the parent of a node, and its identifier.

Returns:

A set with the given start item and all its parents.