KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > com > hp > hpl > jena > graph > Node_NULL


1 /*
2  * (c) Copyright 2002, 2003, 2004, 2005 Hewlett-Packard Development Company, LP
3  * [see end of file]
4  */
5
6 package com.hp.hpl.jena.graph;
7
8 /**
9     A Node_ANY (there should be only one) is a meta-node that is used to stand
10     for any other node in a query.
11     @author kers
12 */
13
14 public class Node_NULL extends Node_Concrete
15     {
16     /* package */ Node_NULL() { super( "" ); }
17     
18     /** Node_NULL's are equal to no null nodes; strictly speaking,
19      * this incorrect but suits our purposes. really want an isNull
20      * method on Node but that's too much surgery. */
21     
22     public boolean equals( Object JavaDoc other )
23         { return other instanceof Node_NULL; }
24         
25     public Object JavaDoc visitWith( NodeVisitor v )
26         { return null; }
27                 
28     public String JavaDoc toString()
29         { return "NULL"; }
30     }
31
32 /*
33  * (c) Copyright 2002, 2003, 2004, 2005 Hewlett-Packard Development Company, LP
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  * notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  * notice, this list of conditions and the following disclaimer in the
43  * documentation and/or other materials provided with the distribution.
44  * 3. The name of the author may not be used to endorse or promote products
45  * derived from this software without specific prior written permission.
46  *
47  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
48  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
49  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
50  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
51  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
52  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
53  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
54  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
55  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
56  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
57  */
58
Popular Tags