com.neurosys.menu.service

Class MergeMenus<M extends MenuItem<M>>

java.lang.Object

com.neurosys.menu.service.MergeMenus<M>

public class MergeMenus<M extends MenuItem<M>>
extends Object

Given multiple MenuItems hierarchies; perform a Merge on them. While MenuItem is Comparable, the merge operations strictly look @ MenuItem.getName() and by default this is case-insensitive.
All references to Primary Hierarchy indicate the first MenuItem to be merged, and secondary hierarchy to the second MenuItem.

Author:

Arjun Dhar

Constructor Summary

Constructors

Constructor and Description
MergeMenus()

Method Summary

Modifier and Type	Method and Description
org.apache.commons.collections.Transformer	getMenuIdTranslator() It maybe possible that the identifiers of 2 nodes may not match but imply the same node.
Comparator<M>	getSort() An Optional Sorting algorithm to apply on merged children
boolean	merge(M hierarchy1, M hierarchy2, Set<String> searchedSet) Merge two MenuItem; merge the second hierarchy into the first (Fold Left operation).
void	normalize(M hierarchyTobeNormalized) Apply the menuIdTranslator to the MenuItem
void	setMenuIdTranslator(org.apache.commons.collections.Transformer menuIdTranslator) It maybe possible that the identifiers of 2 nodes may not match but imply the same node.
void	setSort(Comparator<M> sort) An Optional Sorting algorithm to apply on merged children

Methods inherited from class java.lang.Object

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

Constructor Detail

MergeMenus

public MergeMenus()

Method Detail

normalize

public void normalize(M hierarchyTobeNormalized)

Apply the menuIdTranslator to the MenuItem

Parameters:

hierarchyTobeNormalized - as MenuItem

merge

public boolean merge(M hierarchy1,
                     M hierarchy2,
                     Set<String> searchedSet)

Merge two MenuItem; merge the second hierarchy into the first (Fold Left operation). Common nodes will retain value from hierarchy1.
Note: Menu MenuItem.names are case insensitive while comparing. Merge Algorithm: Compare the 2nd hierarchy root(s) to every element till they find a match (MenuItems should be normalized before comparison). if they find a match, then the elements of the 2nd hierarchy nodes under the matched parent are recursively matched, till all items are merged. If @ any level matches are not found then the node with its children is appended.
No matching node will result in an Exception being thrown.

Parameters:

hierarchy1 - as MenuItem

hierarchy2 - as MenuItem

searchedSet - as Optional scratch space.During the merge process some combinations of searches are repeated, improve efficiency by eliminating search paths once discovered. Improves efficiency by 5 to 6 times on small trees of depth 3; on larger trees could be more significant.

Returns:

boolean; true if a place was found for hierarchy2 to be merged else false

getMenuIdTranslator

public org.apache.commons.collections.Transformer getMenuIdTranslator()

It maybe possible that the identifiers of 2 nodes may not match but imply the same node.
If available (optional), the translator will be applied for the normalization and comparison of the menu ids ie MenuItem.getName() The Transformer expects to take in a MenuItem (with a name of type understood by the secondary Hierarchy and translated to a MenuItem with a understood by the first Hierarchy)
Note: By default MenuItem.compareTo(MenuItem) is case insensitive on the name.

setMenuIdTranslator

public void setMenuIdTranslator(org.apache.commons.collections.Transformer menuIdTranslator)

It maybe possible that the identifiers of 2 nodes may not match but imply the same node.
If available (optional), the translator will be applied for the normalization and comparison of the menu ids ie MenuItem.getName() The Transformer expects to take in a MenuItem (with a name of type understood by the secondary Hierarchy and translated to a MenuItem with a understood by the first Hierarchy)
Note: By default MenuItem.compareTo(MenuItem) is case insensitive on the name.

getSort

public Comparator<M> getSort()

An Optional Sorting algorithm to apply on merged children

setSort

public void setSort(Comparator<M> sort)

An Optional Sorting algorithm to apply on merged children