com.communote.common.util

Class OrderableManager<T extends Orderable>

java.lang.Object

com.communote.common.util.OrderableManager<T>

Type Parameters:

T - the type of the orderables

public class OrderableManager<T extends Orderable>
extends Object

Thread-safe manager for orderable objects which provides convenience methods for accessing the sorted orderables.

Author:

Communote GmbH - http://www.communote.com/

Constructor Summary

Constructors

Constructor and Description
OrderableManager(Comparator<Orderable> comparator, boolean allowDuplicates) Create a manager for orderable items.

Method Summary

Modifier and Type	Method and Description
boolean	add(T orderable) Add a new item.
List<T>	getAll()
T	getFirst()
T	getLast()
boolean	isAllowDuplicates()
boolean	remove(T orderable) Remove a previously added item.

Methods inherited from class java.lang.Object

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

Constructor Detail

OrderableManager

public OrderableManager(Comparator<Orderable> comparator,
                        boolean allowDuplicates)

Create a manager for orderable items.

Parameters:

comparator - the comparator to use for sorting the added items.

allowDuplicates - whether duplicates should be allowed when adding new items. If false a new item will not be added if it already exists.

Method Detail

add

public boolean add(T orderable)

Add a new item. If duplicates are not allowed the new item will not be added if it already exists.

Parameters:

orderable - the item to add

Returns:

true if the item was added or false if the item was null or already exists and duplicates are not allowed.

getAll

public List<T> getAll()

Returns:

an unmodifiable list of all added items. The list is sorted with the comparator passed to the constructor.

getFirst

public T getFirst()

Returns:

the first item of the sorted list of all added items or null if no items were added

getLast

public T getLast()

Returns:

the last item of the sorted list of all added items or null if no items were added

isAllowDuplicates

public boolean isAllowDuplicates()

Returns:

whether duplicates are allowed

remove

public boolean remove(T orderable)

Remove a previously added item. If duplicates are allowed the first matching will be removed.

Parameters:

orderable - the item to remove

Returns:

true if the item was contained, false otherwise