com.vaadin.data.provider.

Class HierarchyMapper<T,F>

  • Type Parameters:

    T - the data type

    F - the filter type

    All Implemented Interfaces:

    DataGenerator<T>, Serializable


    public class HierarchyMapper<T,F>
extends Object
implements DataGenerator<T>

    Mapper for hierarchical data.

    Keeps track of the expanded nodes, and size of of the subtrees for each expanded node.

    This class is framework internal implementation details, and can be changed / moved at any point. This means that you should not directly use this for anything.

    Since:

    8.1

    Author:

    Vaadin Ltd

    See Also:

    Serialized Form

    • Constructor Detail

      • HierarchyMapper

        public HierarchyMapper(HierarchicalDataProvider<T,F> provider)

        Constructs a new HierarchyMapper.

        Parameters:

        provider - the hierarchical data provider for this mapper

    • Method Detail

      • getTreeSize

        public int getTreeSize()

        Returns the size of the currently expanded hierarchy.

        Returns:

        the amount of available data

      • getParentIndex

        public Integer getParentIndex(T item)

        Finds the index of the parent of the item in given target index.

        Parameters:

        item - the item to get the parent of

        Returns:

        the parent index or a negative value if the parent is not found

      • isExpanded

        public boolean isExpanded(T item)

        Returns whether the given item is expanded.

        Parameters:

        item - the item to test

        Returns:

        true if item is expanded; false if not

      • expand

        public Range expand(T item,
                    Integer position)

        Expands the given item.

        Parameters:

        item - the item to expand

        position - the index of the item

        Returns:

        range of rows added by expanding the item

      • doExpand

        @Deprecated
public Range doExpand(T item,
                                  Optional<Integer> position)

        Deprecated. Use expand(Object, Integer) instead.

        Expands the given item.

        Parameters:

        item - the item to expand

        position - the index of item

        Returns:

        range of rows added by expanding the item

      • collapse

        public Range collapse(T item,
                      Integer position)

        Collapses the given item.

        Parameters:

        item - the item to collapse

        position - the index of the item

        Returns:

        range of rows removed by collapsing the item

      • doCollapse

        @Deprecated
public Range doCollapse(T item,
                                    Optional<Integer> position)

        Deprecated. Use collapse(Object, Integer) instead.

        Collapses the given item.

        Parameters:

        item - the item to collapse

        position - the index of item

        Returns:

        range of rows removed by collapsing the item

      • generateData

        public void generateData(T item,
                         JsonObject jsonObject)

        Description copied from interface: DataGenerator

        Adds custom data for the given item to its serialized JsonObject representation. This JSON object will be sent to client-side DataProvider.

        Specified by:

        generateData in interface DataGenerator<T>

        Parameters:

        item - the data item being serialized

        jsonObject - the JSON object being sent to the client

      • getItemCollapseAllowedProvider

        public ItemCollapseAllowedProvider<T> getItemCollapseAllowedProvider()

        Gets the current item collapse allowed provider.

        Returns:

        the item collapse allowed provider

      • setItemCollapseAllowedProvider

        public void setItemCollapseAllowedProvider(ItemCollapseAllowedProvider<T> itemCollapseAllowedProvider)

        Sets the current item collapse allowed provider.

        Parameters:

        itemCollapseAllowedProvider - the item collapse allowed provider

      • getInMemorySorting

        public Comparator<T> getInMemorySorting()

        Gets the current in-memory sorting.

        Returns:

        the in-memory sorting

      • setInMemorySorting

        public void setInMemorySorting(Comparator<T> inMemorySorting)

        Sets the current in-memory sorting. This will cause the hierarchy to be constructed again.

        Parameters:

        inMemorySorting - the in-memory sorting

      • getBackEndSorting

        public List<QuerySortOrder> getBackEndSorting()

        Gets the current back-end sorting.

        Returns:

        the back-end sorting

      • setBackEndSorting

        public void setBackEndSorting(List<QuerySortOrder> backEndSorting)

        Sets the current back-end sorting. This will cause the hierarchy to be constructed again.

        Parameters:

        backEndSorting - the back-end sorting

      • getFilter

        public F getFilter()

        Gets the current filter.

        Returns:

        the filter

      • setFilter

        public void setFilter(Object filter)

        Sets the current filter. This will cause the hierarchy to be constructed again.

        Parameters:

        filter - the filter

      • getDataProvider

        public HierarchicalDataProvider<T,F> getDataProvider()

        Gets the HierarchicalDataProvider for this HierarchyMapper.

        Returns:

        the hierarchical data provider

      • hasChildren

        public boolean hasChildren(T item)

        Returns whether given item has children.

        Parameters:

        item - the node to test

        Returns:

        true if node has children; false if not

      • fetchItems

        public Stream<T> fetchItems(Range range)

        Gets a stream of items in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.

        Parameters:

        range - the requested item range

        Returns:

        the stream of items

      • fetchItems

        public Stream<T> fetchItems(T parent,
                            Range range)

        Gets a stream of children for the given item in the form of a flattened hierarchy from the back-end and filter the wanted results from the list.

        Parameters:

        parent - the parent item for the fetch

        range - the requested item range

        Returns:

        the stream of items

      • getParentOfItem

        protected T getParentOfItem(T item)

        Find parent for the given item among open folders.

        Parameters:

        item - the item

        Returns:

        parent item or null for root items or if the parent is closed

      • removeChildren

        protected void removeChildren(Object id)

        Removes all children of an item identified by a given id. Items removed by this method as well as the original item are all marked to be collapsed. May be overridden in subclasses for removing obsolete data to avoid memory leaks.

        Parameters:

        id - the item id

      • getIndexOf

        public Optional<Integer> getIndexOf(T target)

        Finds the current index of given object. This is based on a search in flattened version of the hierarchy.

        Parameters:

        target - the target object to find

        Returns:

        optional index of given object

      • registerChildren

        protected void registerChildren(T parent,
                                List<T> childList)

        Register parent and children items into inner structures. May be overridden in subclasses.

        Parameters:

        parent - the parent item

        childList - list of parents children to be registered.

      • destroyAllData

        public void destroyAllData()

        Description copied from interface: DataGenerator

        Informs the DataGenerator that all data has been dropped. This method should clean up any unneeded information stored for items.

        Specified by:

        destroyAllData in interface DataGenerator<T>