Package com.helger.commons.hierarchy

Interface IHasChildren<CHILDTYPE>

Type Parameters:

CHILDTYPE - The type of the children.

All Known Subinterfaces:

IHasChildrenRecursive<CHILDTYPE>, IHasChildrenSorted<CHILDTYPE>

public interface IHasChildren<CHILDTYPE>

A simple interface, indicating that an item has direct children.

Author:

Philip Helger

Method Summary

Modifier and Type	Method	Description
default void	forAllChildren(Consumer<? super CHILDTYPE> aConsumer)	Perform something on all children (if any). Note: use this only for reading.
default void	forAllChildren(Predicate<? super CHILDTYPE> aFilter, Consumer<? super CHILDTYPE> aConsumer)	Iterate all direct children (if at least one is present) and invoke the provided consumer if the passed predicate is fulfilled. Note: use this only for reading.
default EContinue	forAllChildrenBreakable(Function<? super CHILDTYPE,EContinue> aConsumer)	Perform something on all children (if any). Note: use this only for reading.
default <DSTTYPE> void	forAllChildrenMapped(Predicate<? super CHILDTYPE> aFilter, Function<? super CHILDTYPE,? extends DSTTYPE> aMapper, Consumer<? super DSTTYPE> aConsumer)	Iterate all direct children (if at least one is present) and invoked the provided consumer if the passed predicate is fulfilled. Note: use this only for reading.
ICommonsCollection<? extends CHILDTYPE>	getAllChildren()
int	getChildCount()
ICommonsIterable<? extends CHILDTYPE>	getChildren()
default boolean	hasChildren()
default boolean	hasNoChildren()

Method Detail

hasChildren

default boolean hasChildren()

Returns:

true if this item has direct children, false otherwise.

hasNoChildren

default boolean hasNoChildren()

Returns:

true if this item has no direct children, false otherwise.

getChildCount

@Nonnegative
int getChildCount()

Returns:

The number of contained direct children. Always ≥ 0.

getAllChildren

@Nullable
@ReturnsMutableCopy
ICommonsCollection<? extends CHILDTYPE> getAllChildren()

Returns:

A collection of all direct child elements. May be null if no children are contained. This method should always return a copy of the collection to avoid ConcurrentModificationException when modifying it.

See Also:

hasChildren(), getChildren()

getChildren

@Nullable
ICommonsIterable<? extends CHILDTYPE> getChildren()

Returns:

An iterable over all direct children. May be null if no children are contained. Compared to getAllChildren() this method is not supposed to create a copy of the underlying container but instead return the iterable only. Be careful when using this method to modify a collection - it will lead to a ConcurrentModificationException.

Since:

9.0.0

See Also:

hasChildren(), getChildren()

forAllChildren

default void forAllChildren(@Nonnull
                            Consumer<? super CHILDTYPE> aConsumer)

Perform something on all children (if any).
Note: use this only for reading. Writing operations will potentially cause concurrent modification exceptions!

Parameters:

aConsumer - The consumer to be invoked. May not be null.

forAllChildrenBreakable

@Nonnull
default EContinue forAllChildrenBreakable(@Nonnull
                                          Function<? super CHILDTYPE,EContinue> aConsumer)

Perform something on all children (if any).
Note: use this only for reading. Writing operations will potentially cause concurrent modification exceptions!

Parameters:

aConsumer - The breakable consumer to be invoked. May not be null.

Returns:

EContinue.BREAK if iteration was stopped, EContinue.CONTINUE otherwise.

forAllChildren

default void forAllChildren(@Nonnull
                            Predicate<? super CHILDTYPE> aFilter,
                            @Nonnull
                            Consumer<? super CHILDTYPE> aConsumer)

Iterate all direct children (if at least one is present) and invoke the provided consumer if the passed predicate is fulfilled.
Note: use this only for reading. Writing operations will potentially cause concurrent modification exceptions!

Parameters:

aFilter - The filter that is applied to all children. May not be null.

aConsumer - The consumer to be invoked for all children matching the filter. May not be null.

forAllChildrenMapped

default <DSTTYPE> void forAllChildrenMapped(@Nonnull
                                            Predicate<? super CHILDTYPE> aFilter,
                                            @Nonnull
                                            Function<? super CHILDTYPE,? extends DSTTYPE> aMapper,
                                            @Nonnull
                                            Consumer<? super DSTTYPE> aConsumer)

Iterate all direct children (if at least one is present) and invoked the provided consumer if the passed predicate is fulfilled.
Note: use this only for reading. Writing operations will potentially cause concurrent modification exceptions!

Type Parameters:

DSTTYPE - The destination data type.

Parameters:

aFilter - The filter that is applied to all children. May not be null.

aMapper - The mapping function from child type to the target type. May not be null.

aConsumer - The consumer to be invoked for all target types matching the filter. May not be null.