1 //******************************************************************************
2 //
3 // File: ObjectArrayBuf_1.java
4 // Package: edu.rit.mp.buf
5 // Unit: Class edu.rit.mp.buf.ObjectArrayBuf_1
6 //
7 // This Java source file is copyright (C) 2009 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.mp.buf;
41
42 import edu.rit.mp.Buf;
43 import edu.rit.pj.reduction.ObjectOp;
44 import edu.rit.pj.reduction.Op;
45 import edu.rit.util.Range;
46
47 /**
48 * Class ObjectArrayBuf_1 provides a buffer for an array of object items sent or
49 * received using the Message Protocol (MP). The array element stride must be 1.
50 * While an instance of class ObjectArrayBuf may be constructed directly,
51 * normally you will use a factory method in class {@linkplain
52 * edu.rit.mp.ObjectBuf ObjectBuf}. See that class for further information.
53 *
54 * @param <T> Data type of the objects in the buffer.
55 * @author Alan Kaminsky
56 * @version 23-Mar-2009
57 */
58 @SuppressWarnings("unchecked")
59 public class ObjectArrayBuf_1<T>
60 extends ObjectArrayBuf<T> {
61
62 // Exported constructors.
63 /**
64 * Construct a new object array buffer.
65 *
66 * @param theArray Array.
67 * @param theRange Range of array elements to include in the buffer. The
68 * stride is assumed to be 1.
69 */
70 public ObjectArrayBuf_1(T[] theArray,
71 Range theRange) {
72 super(theArray, theRange);
73 }
74
75 // Exported operations.
76 /**
77 * {@inheritDoc}
78 *
79 * Obtain the given item from this buffer.
80 * <P>
81 * The <code>get()</code> method must not block the calling thread; if it does,
82 * all message I/O in MP will be blocked.
83 */
84 public T get(int i) {
85 return myArray[myArrayOffset + i];
86 }
87
88 /**
89 * Store the given item in this buffer.
90 * <P>
91 * The <code>put()</code> method must not block the calling thread; if it does,
92 * all message I/O in MP will be blocked.
93 *
94 * @param i Item index in the range 0 .. <code>length()</code>-1.
95 * @param item Item to be stored at index <code>i</code>.
96 */
97 public void put(int i,
98 T item) {
99 myArray[myArrayOffset + i] = item;
100 reset();
101 }
102
103 /**
104 * {@inheritDoc}
105 *
106 * Create a buffer for performing parallel reduction using the given binary
107 * operation. The results of the reduction are placed into this buffer.
108 * @exception ClassCastException (unchecked exception) Thrown if this
109 * buffer's element data type and the given binary operation's argument data
110 * type are not the same.
111 */
112 public Buf getReductionBuf(Op op) {
113 return new ObjectArrayReductionBuf_1<T>(myArray, myRange, (ObjectOp<T>) op, this);
114 }
115
116 }