org.codefx.libfx.collection.tree.navigate

Interface TreeNavigator<E>

Type Parameters:

E - the type of elements contained in the tree

All Known Implementing Classes:

ComponentHierarchyNavigator, JComponentHierarchyNavigator, SceneGraphNavigator

public interface TreeNavigator<E>

A tree navigator allows to walk through a tree (i.e. a connected, directed, acyclic graph).

This interface can be implemented to navigate arbitrary tree-like data structures without requiring them to implement a specific interface.

The navigation relies on child nodes having some fixed order so they can be accessed via an index.

Method Summary

Modifier and Type	Method and Description
Optional<E>	getChild(E parent, int childIndex)
OptionalInt	getChildIndex(E node)
int	getChildrenCount(E parent)
Optional<E>	getParent(E child)

Method Detail

getParent

Optional<E> getParent(E child)

Parameters:

child - an node in the tree

Returns:

the child's parent; if it is the root, it doesn't have a parent, so empty is returned

getChildIndex

OptionalInt getChildIndex(E node)

Parameters:

node - a node in the tree

Returns:

the index of the node within the list of children of its parent; if it is the root, it doesn't have a parent, so empty is returned

getChildrenCount

int getChildrenCount(E parent)

Parameters:

parent - a node in the tree

Returns:

the number of children the node has

getChild

Optional<E> getChild(E parent,
                     int childIndex)

Parameters:

parent - a node in the tree

childIndex - a non-negative number specifying the index of the requested child

Returns:

the child of the node with the child index; if no such child exists (e.g. because no children exist) empty is returned