org.netbeans.spi.viewmodel.TreeModel Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.netbeans.spi.viewmodel;
/**
* Defines data model for tree.
*
* @author Jan Jancura
*/
public interface TreeModel extends Model {
/**
* Constant for root node. This root node should be used if root node
* does not represent any valuable information and should not be visible in
* tree.
*/
public static final String ROOT = "Root";
/**
* Returns the root node of the tree or null, if the tree is empty.
*
* @return the root node of the tree or null
*/
public abstract Object getRoot ();
/**
* Returns children for given parent on given indexes.
* This method works in pair with {@link #getChildrenCount}, the to
* parameter is up to the value that is returned from {@link #getChildrenCount}.
* If the list of children varies over time, the implementation code
* needs to pay attention to bounds and check the from and
* to parameters, especially if {@link #getChildrenCount}
* returns Integer.MAX_VALUE. Caching of the children between
* {@link #getChildrenCount} and {@link #getChildren} can be used as well,
* if necessary.
*
* @param parent a parent of returned nodes
* @param from a start index
* @param to a end index
*
* @throws UnknownTypeException if this TreeModel implementation is not
* able to resolve children for given node type
*
* @return children for given parent on given indexes
* @see #getChildrenCount
*/
public abstract Object[] getChildren (Object parent, int from, int to)
throws UnknownTypeException;
/**
* Returns true if node is leaf.
*
* @throws UnknownTypeException if this TreeModel implementation is not
* able to resolve children for given node type
* @return true if node is leaf
*/
public abstract boolean isLeaf (Object node) throws UnknownTypeException;
/**
* Returns the number of children for given node.
* This method works in pair with {@link #getChildren}, which gets
* this returned value (or less) as the to parameter. This method
* is always called before a call to {@link #getChildren}. This method can
* return e.g. Integer.MAX_VALUE when all children should be
* loaded.
*
* @param node the parent node
* @throws UnknownTypeException if this TreeModel implementation is not
* able to resolve children for given node type
*
* @return the children count
* @since 1.1
* @see #getChildren
*/
public abstract int getChildrenCount (Object node)
throws UnknownTypeException;
/**
* Registers given listener.
*
* @param l the listener to add
*/
public abstract void addModelListener (ModelListener l);
/**
* Unregisters given listener.
*
* @param l the listener to remove
*/
public abstract void removeModelListener (ModelListener l);
}