org.mapsforge.poi.storage

Class DoubleLinkedPoiCategory

java.lang.Object

org.mapsforge.poi.storage.DoubleLinkedPoiCategory

All Implemented Interfaces:

PoiCategory

public class DoubleLinkedPoiCategory
extends Object
implements PoiCategory

A POI category representation that stores a node, its parent node and its child nodes.

Constructor Summary

Constructors

Constructor and Description
DoubleLinkedPoiCategory(String title, PoiCategory parent) Creates a new category without knowing its position in the final category tree.
DoubleLinkedPoiCategory(String title, PoiCategory parent, int id) Creates a new category.

Method Summary

Methods

Modifier and Type	Method and Description
static int	calculateCategoryIDs(DoubleLinkedPoiCategory rootNode, int maxValue) This method calculates a unique ID for all nodes in the tree.
Collection<PoiCategory>	deepChildren()
Collection<PoiCategory>	getChildren()
static String	getGraphVizString(DoubleLinkedPoiCategory rootNode) Generates a GraphViz source representation as a tree having the current node as its root.
int	getID() Make sure you call calculateCategoryIDs(DoubleLinkedPoiCategory, int) first.
PoiCategory	getParent()
String	getTitle()
void	setParent(PoiCategory parent) Sets the category's parent category.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

DoubleLinkedPoiCategory

public DoubleLinkedPoiCategory(String title,
                       PoiCategory parent)

Creates a new category without knowing its position in the final category tree. If all categories have been created you have to call calculateCategoryIDs(DoubleLinkedPoiCategory, int) to assign the IDs.

Parameters:

title - The category's unique title.

parent - The category's parent category. For creating a root node, set the parent to null.

DoubleLinkedPoiCategory

public DoubleLinkedPoiCategory(String title,
                       PoiCategory parent,
                       int id)

Creates a new category. This constructor should only be called from PoiCategoryManager when reading a category configuration from a database or XML file. Otherwise call DoubleLinkedPoiCategory(String, PoiCategory).

Parameters:

title - The category's unique title.

parent - The category's parent category. For creating a root node, set the parent to null.

id - The category's position in the tree determined by left-order-dfs-traversal.

Method Detail

calculateCategoryIDs

public static int calculateCategoryIDs(DoubleLinkedPoiCategory rootNode,
                       int maxValue)

This method calculates a unique ID for all nodes in the tree. For each node's 'n' ID named 'ID_'n at depth 'd' the following invariants must be true:

• ID > max(ID of all child nodes)
• All nodes' IDs left of n must be < ID_n.
• All nodes' IDs right of n must be > ID_n.

Parameters:

rootNode - The tree's root node. (Any other node will result in invalid IDs!)

maxValue - Global maximum ID.

Returns:

The root node's ID.

deepChildren

public Collection<PoiCategory> deepChildren()

Specified by:

deepChildren in interface PoiCategory

Returns:

All child categories of the category, including their children.

getChildren

public Collection<PoiCategory> getChildren()

Specified by:

getChildren in interface PoiCategory

Returns:

All child categories of the category.

getGraphVizString

public static String getGraphVizString(DoubleLinkedPoiCategory rootNode)

Generates a GraphViz source representation as a tree having the current node as its root.

Parameters:

rootNode - The resulting graph's root node. (You can use any sub node to get a sub-graph).

Returns:

a GraphViz source representation as a tree having the current node as its root.

getID

public int getID()

Make sure you call calculateCategoryIDs(DoubleLinkedPoiCategory, int) first.

Specified by:

getID in interface PoiCategory

Returns:

The node's ID.

getParent

public PoiCategory getParent()

Specified by:

getParent in interface PoiCategory

Returns:

The parent category of this category or null if this category has no parent.

getTitle

public String getTitle()

Specified by:

getTitle in interface PoiCategory

Returns:

The title of this category.

setParent

public void setParent(PoiCategory parent)

Sets the category's parent category.

Specified by:

setParent in interface PoiCategory

Parameters:

parent - The category to be set as parent.

toString

public String toString()

Overrides:

toString in class Object