1 ////////////////////////////////////////////////////////////////////////////////
2 // MillScript: an Open Spice interpreter and batch website creation tool
3 // Copyright (C) 2001-2004 Open World Ltd
4 //
5 // This file is part of MillScript.
6 //
7 // MillScript is free software; you can redistribute it and/or modify it under
8 // the terms of the GNU General Public License as published by the Free
9 // Software Foundation; either version 2 of the License, or (at your option)
10 // any later version.
11 //
12 // MillScript is distributed in the hope that it will be useful, but WITHOUT
13 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 // more details.
16 //
17 // You should have received a copy of the GNU General Public License along with
18 // MillScript; if not, write to the Free Software Foundation, Inc., 59 Temple
19 // Place, Suite 330, Boston, MA 02111-1307 USA
20 ////////////////////////////////////////////////////////////////////////////////
21 package org.millscript.millscript.datatypes;
22
23 import java.util.Iterator;
24 import java.util.NoSuchElementException;
25
26 /**
27 * An <code>Iterator</code> that iterates over no items. This is used in the
28 * implmentation of {@link NullSet}.
29 *
30 * @deprecated As of MillScript 10.2.0, this functionallity has been subsumed
31 * by the MillScript-Util project and it's Map API, see
32 * {@link org.millscript.commons.util.iterator.NullMapIterator}.
33 */
34 @Deprecated
35 public class NullIterator implements Iterator< Object > {
36
37 /**
38 * Returns <code>false</code>, as this iterator never has any values.
39 *
40 * @return <code>false</code>, this iterator never has any values.
41 * @see java.util.Iterator#hasNext()
42 */
43 public boolean hasNext() {
44 return false;
45 }
46
47 /**
48 * @see java.util.Iterator#next()
49 */
50 public Object next() {
51 // This method is invalid for a Null iterator, as we don't have any
52 // values to iterate over
53 throw new NoSuchElementException( "a null iterator has no values" );
54 }
55
56 /**
57 * @see java.util.Iterator#remove()
58 */
59 public void remove() {
60 // This method is invalid for a Null iterator, as we don't have any
61 // values to remove
62 throw new UnsupportedOperationException();
63 }
64 }