1 /*

     2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package javax.swing.tree;

    27 

    28 import java.util.Enumeration;

    29 

    30 /**

    31  * Defines the requirements for an object that can be used as a

    32  * tree node in a JTree.

    33  * <p>

    34  * Implementations of <code>TreeNode</code> that override <code>equals</code>

    35  * will typically need to override <code>hashCode</code> as well.  Refer

    36  * to {@link javax.swing.tree.TreeModel} for more information.

    37  *

    38  * For further information and examples of using tree nodes,

    39  * see <a

    40  href="http://docs.oracle.com/javase/tutorial/uiswing/components/tree.html">How to Use Tree Nodes</a>

    41  * in <em>The Java Tutorial.</em>

    42  *

    43  * @author Rob Davis

    44  * @author Scott Violet

    45  */

    46 

    47 public interface TreeNode

    48 {

    49     /**

    50      * Returns the child <code>TreeNode</code> at index

    51      * <code>childIndex</code>.

    52      *

    53      * @param   childIndex  index of child

    54      * @return              the child node at given index

    55      */

    56     TreeNode getChildAt(int childIndex);

    57 

    58     /**

    59      * Returns the number of children <code>TreeNode</code>s the receiver

    60      * contains.

    61      *

    62      * @return              the number of children the receiver contains

    63      */

    64     int getChildCount();

    65 

    66     /**

    67      * Returns the parent <code>TreeNode</code> of the receiver.

    68      *

    69      * @return              the parent of the receiver

    70      */

    71     TreeNode getParent();

    72 

    73     /**

    74      * Returns the index of <code>node</code> in the receivers children.

    75      * If the receiver does not contain <code>node</code>, -1 will be

    76      * returned.

    77      *

    78      * @param   node        node to be loked for

    79      * @return              index of specified node

    80      */

    81     int getIndex(TreeNode node);

    82 

    83     /**

    84      * Returns true if the receiver allows children.

    85      *

    86      * @return              whether the receiver allows children

    87      */

    88     boolean getAllowsChildren();

    89 

    90     /**

    91      * Returns true if the receiver is a leaf.

    92      *

    93      * @return              whether the receiver is a leaf

    94      */

    95     boolean isLeaf();

    96 

    97     /**

    98      * Returns the children of the receiver as an <code>Enumeration</code>.

    99      *

   100      * @return              the children of the receiver as an {@code Enumeration}

   101      */

   102     Enumeration<? extends TreeNode> children();

   103 }