com.helger.commons.hierarchy

Class ChildrenProviderHasChildren<CHILDTYPE extends IHasChildren<CHILDTYPE>>

java.lang.Object

com.helger.commons.hierarchy.ChildrenProviderHasChildren<CHILDTYPE>

Type Parameters:

CHILDTYPE - The data type of the child objects.

All Implemented Interfaces:

IChildrenProvider<CHILDTYPE>

Direct Known Subclasses:

ChildrenProviderHasChildrenSorted, ChildrenProviderHasChildrenSorting, ChildrenProviderHasChildrenWithID

@Immutable
public class ChildrenProviderHasChildren<CHILDTYPE extends IHasChildren<CHILDTYPE>>
extends Object
implements IChildrenProvider<CHILDTYPE>

A standard implementation of the IChildrenProvider interface that works with all types that implement IHasChildren.

Author:

Philip Helger

Constructor Summary

Constructors

Constructor and Description
ChildrenProviderHasChildren()

Method Summary

Methods

Modifier and Type	Method and Description
Collection<? extends CHILDTYPE>	getAllChildren(CHILDTYPE aCurrent) Get the children of the passed object.
int	getChildCount(CHILDTYPE aCurrent)
boolean	hasChildren(CHILDTYPE aCurrent) Check if an item has children.

Methods inherited from class java.lang.Object

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

Constructor Detail

ChildrenProviderHasChildren

public ChildrenProviderHasChildren()

Method Detail

hasChildren

public final boolean hasChildren(@Nullable
                  CHILDTYPE aCurrent)

Description copied from interface: IChildrenProvider

Check if an item has children.

Specified by:

hasChildren in interface IChildrenProvider<CHILDTYPE extends IHasChildren<CHILDTYPE>>

Parameters:

aCurrent - The object to determine the children of. No null or non- null constraint possible.

Returns:

true if this item has children, false otherwise.

getChildCount

@Nonnegative
public final int getChildCount(@Nullable
                            CHILDTYPE aCurrent)

Specified by:

getChildCount in interface IChildrenProvider<CHILDTYPE extends IHasChildren<CHILDTYPE>>

Parameters:

aCurrent - The object to determine the children count of. No null or non- null constraint possible.

Returns:

The number of contained direct children. Always ≥ 0.

getAllChildren

@Nullable
public Collection<? extends CHILDTYPE> getAllChildren(@Nullable
                                                      CHILDTYPE aCurrent)

Description copied from interface: IChildrenProvider

Get the children of the passed object.

Specified by:

getAllChildren in interface IChildrenProvider<CHILDTYPE extends IHasChildren<CHILDTYPE>>

Parameters:

aCurrent - The object to determine the children of. No null or non-null constraint possible.

Returns:

The child objects, or null if there are no children. If null is passed, the resolver is expected to return any possible top level (root) elements. This method may NOT return null if the call to IChildrenProvider.hasChildren(Object) with the same object returned true.