001// Copyright 2011 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry5.tree; 016 017/** 018 * Tracks which <em>leaf</em> nodes of a {@link TreeModel} are currently selected. The {@linkplain DefaultTreeSelectionModel default 019 * implementation} simply stores a set of {@linkplain TreeNode#getId() unique node 020 * ids} to identify selected nodes. The selection model is updated whenever the user clicks on the label for a leaf node. 021 * <p/> 022 * In the future, new methods may be added that will support selection of folders as well as leafs, and define the rules for 023 * how selections and de-selections propagate down to children or up to parents. 024 * 025 * @param <T> type of node 026 * @see org.apache.tapestry5.corelib.components.Tree 027 * @since 5.3 028 */ 029public interface TreeSelectionModel<T> 030{ 031 032 /** 033 * Returns {@code true}, if the given node is selected. 034 * 035 * @param node node to check 036 */ 037 boolean isSelected(TreeNode<T> node); 038 039 /** 040 * Selects a node. 041 * 042 * @param node node to select 043 */ 044 void select(TreeNode<T> node); 045 046 /** 047 * Unselects a node. 048 * 049 * @param node node to unselect 050 */ 051 void unselect(TreeNode<T> node); 052 053 /** 054 * Clears the selection. 055 */ 056 void clear(); 057}