1 //******************************************************************************
2 //
3 // File: ItemHolder.java
4 // Package: edu.rit.pj
5 // Unit: Class edu.rit.pj.ItemHolder
6 //
7 // This Java source file is copyright (C) 2007 by Alan Kaminsky. All rights
8 // reserved. For further information, contact the author, Alan Kaminsky, at
9 // ark@cs.rit.edu.
10 //
11 // This Java source file is part of the Parallel Java Library ("PJ"). PJ is free
12 // software; you can redistribute it and/or modify it under the terms of the GNU
13 // General Public License as published by the Free Software Foundation; either
14 // version 3 of the License, or (at your option) any later version.
15 //
16 // PJ is distributed in the hope that it will be useful, but WITHOUT ANY
17 // WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
18 // A PARTICULAR PURPOSE. See the GNU General Public License for more details.
19 //
20 // Linking this library statically or dynamically with other modules is making a
21 // combined work based on this library. Thus, the terms and conditions of the GNU
22 // General Public License cover the whole combination.
23 //
24 // As a special exception, the copyright holders of this library give you
25 // permission to link this library with independent modules to produce an
26 // executable, regardless of the license terms of these independent modules, and
27 // to copy and distribute the resulting executable under terms of your choice,
28 // provided that you also meet, for each linked independent module, the terms
29 // and conditions of the license of that module. An independent module is a module
30 // which is not derived from or based on this library. If you modify this library,
31 // you may extend this exception to your version of the library, but you are not
32 // obligated to do so. If you do not wish to do so, delete this exception
33 // statement from your version.
34 //
35 // A copy of the GNU General Public License is provided in the file gpl.txt. You
36 // may also obtain a copy of the GNU General Public License on the World Wide
37 // Web at http://www.gnu.org/licenses/gpl.html.
38 //
39 //******************************************************************************
40 package edu.rit.pj;
41
42 import java.io.Externalizable;
43 import java.io.IOException;
44 import java.io.ObjectInput;
45 import java.io.ObjectOutput;
46 import java.io.Serial;
47
48 /**
49 * Class ItemHolder provides an object that holds one item to be processed by a
50 * {@linkplain ParallelIteration} along with associated information.
51 *
52 * @param <T> Data type of the items iterated over.
53 *
54 * @author Alan Kaminsky
55 * @version 07-Oct-2010
56 */
57 @SuppressWarnings("serial")
58 class ItemHolder<T>
59 implements Externalizable {
60
61 // Hidden data members.
62 @Serial
63 private static final long serialVersionUID = -5475933248018589590L;
64
65 // Exported data members.
66 /**
67 * The item itself (may be null).
68 */
69 public T myItem;
70
71 /**
72 * The item's sequence number in the iteration. Sequence numbers start at 0
73 * and increase by 1 for each item.
74 */
75 public int mySequenceNumber;
76
77 // Exported constructors.
78 /**
79 * Construct a new item holder.
80 */
81 public ItemHolder() {
82 }
83
84 // Exported operations.
85 /**
86 * {@inheritDoc}
87 *
88 * Write this object holder to the given object output stream.
89 * @exception IOException Thrown if an I/O error occurred.
90 */
91 public void writeExternal(ObjectOutput out)
92 throws IOException {
93 out.writeObject(myItem);
94 out.writeInt(mySequenceNumber);
95 }
96
97 /**
98 * {@inheritDoc}
99 *
100 * Read this object holder from the given object input stream.
101 * @exception IOException Thrown if an I/O error occurred.
102 * @exception ClassNotFoundException Thrown if the class of the object could
103 * not be found.
104 */
105 @SuppressWarnings("unchecked")
106 public void readExternal(ObjectInput in)
107 throws IOException, ClassNotFoundException {
108 myItem = (T) in.readObject();
109 mySequenceNumber = in.readInt();
110 }
111
112 }