net.sf.mpxj.common

Class HierarchyHelper

java.lang.Object

net.sf.mpxj.common.HierarchyHelper

public class HierarchyHelper
extends Object

Helper methods for working with hierarchical data.

Constructor Summary

Constructors

Constructor and Description
HierarchyHelper()

Method Summary

Modifier and Type	Method and Description
static <K,V> List<V>	sortHierarchy(List<V> list, Function<V,K> getId, Function<V,K> getParentId) Given a list of items, sort the items such that parent items always appear before child items.
static <K,V> List<V>	sortHierarchy(List<V> list, Function<V,K> getId, Function<V,K> getParentId, Comparator<V> comparator) Given a list of items, sort the items such that parent items always appear before child items and ensure child items are sorted.

Methods inherited from class java.lang.Object

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

Constructor Detail

HierarchyHelper

public HierarchyHelper()

Method Detail

sortHierarchy

public static final <K,V> List<V> sortHierarchy(List<V> list,
                                                Function<V,K> getId,
                                                Function<V,K> getParentId)

Given a list of items, sort the items such that parent items always appear before child items. This allows for "one shot" creation of object instances based on this data rather than having to make a second pass to create the hierarchy.

Type Parameters:

K - ID type

V - value type

Parameters:

list - list of items

getId - function to retrieve an item's ID

getParentId - function to retrieve an item's parent ID

Returns:

list sorted to ensure parents appear before children

sortHierarchy

public static final <K,V> List<V> sortHierarchy(List<V> list,
                                                Function<V,K> getId,
                                                Function<V,K> getParentId,
                                                Comparator<V> comparator)

Given a list of items, sort the items such that parent items always appear before child items and ensure child items are sorted. This allows for "one shot" creation of object instances based on this data rather than having to make a second pass to create the hierarchy.

Type Parameters:

K - ID type

V - value type

Parameters:

list - list of items

getId - function to retrieve an item's ID

getParentId - function to retrieve an item's parent ID

comparator - sort order for items within the hierarchy

Returns:

list sorted to ensure parents appear before children