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1   //******************************************************************************
2   //
3   // File:    BooleanMatrixBuf_1.java
4   // Package: edu.rit.mp.buf
5   // Unit:    Class edu.rit.mp.buf.BooleanMatrixBuf_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.
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25  // permission to link this library with independent modules to produce an
26  // executable, regardless of the license terms of these independent modules, and
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28  // provided that you also meet, for each linked independent module, the terms
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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
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33  // statement from your version.
34  //
35  // A copy of the GNU General Public License is provided in the file gpl.txt. You
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39  //******************************************************************************
40  package edu.rit.mp.buf;
41  
42  import java.nio.ByteBuffer;
43  
44  import edu.rit.mp.Buf;
45  import edu.rit.pj.reduction.BooleanOp;
46  import edu.rit.pj.reduction.Op;
47  import edu.rit.util.Range;
48  
49  /**
50   * Class BooleanMatrixBuf_1 provides a buffer for a matrix of Boolean items sent
51   * or received using the Message Protocol (MP). The matrix row and column
52   * strides must both be 1. While an instance of class BooleanMatrixBuf_1 may be
53   * constructed directly, normally you will use a factory method in class
54   * {@linkplain edu.rit.mp.BooleanBuf BooleanBuf}. See that class for further
55   * information.
56   *
57   * @author Alan Kaminsky
58   * @version 05-Apr-2009
59   */
60  public class BooleanMatrixBuf_1
61          extends BooleanMatrixBuf {
62  
63  // Exported constructors.
64      /**
65       * Construct a new Boolean matrix buffer. It is assumed that the rows and
66       * columns of <code>theMatrix</code> are allocated and that each row of
67       * <code>theMatrix</code> has the same number of columns.
68       *
69       * @param theMatrix Matrix.
70       * @param theRowRange Range of rows to include. The stride is assumed to be
71       * 1.
72       * @param theColRange Range of columns to include. The stride is assumed to
73       * be 1.
74       */
75      public BooleanMatrixBuf_1(boolean[][] theMatrix,
76              Range theRowRange,
77              Range theColRange) {
78          super(theMatrix, theRowRange, theColRange);
79      }
80  
81  // Exported operations.
82      /**
83       * {@inheritDoc}
84       *
85       * Obtain the given item from this buffer.
86       * <P>
87       * The <code>get()</code> method must not block the calling thread; if it does,
88       * all message I/O in MP will be blocked.
89       */
90      public boolean get(int i) {
91          return myMatrix[i2r(i) + myLowerRow][i2c(i) + myLowerCol];
92      }
93  
94      /**
95       * {@inheritDoc}
96       *
97       * Store the given item in this buffer.
98       * <P>
99       * The <code>put()</code> method must not block the calling thread; if it does,
100      * all message I/O in MP will be blocked.
101      */
102     public void put(int i,
103             boolean item) {
104         myMatrix[i2r(i) + myLowerRow][i2c(i) + myLowerCol] = item;
105     }
106 
107     /**
108      * {@inheritDoc}
109      *
110      * Create a buffer for performing parallel reduction using the given binary
111      * operation. The results of the reduction are placed into this buffer.
112      * @exception ClassCastException (unchecked exception) Thrown if this
113      * buffer's element data type and the given binary operation's argument data
114      * type are not the same.
115      */
116     public Buf getReductionBuf(Op op) {
117         return new BooleanMatrixReductionBuf_1(myMatrix, myRowRange, myColRange, (BooleanOp) op);
118     }
119 
120 // Hidden operations.
121     /**
122      * {@inheritDoc}
123      *
124      * Send as many items as possible from this buffer to the given byte buffer.
125      * <P>
126      * The <code>sendItems()</code> method must not block the calling thread; if it
127      * does, all message I/O in MP will be blocked.
128      */
129     protected int sendItems(int i,
130             ByteBuffer buffer) {
131         int n = 0;
132         int r = i2r(i);
133         int row = r + myLowerRow;
134         int c = i2c(i);
135         int col = c + myLowerCol;
136         int ncols = Math.min(myColCount - c, buffer.remaining());
137         while (r < myRowCount && ncols > 0) {
138             boolean[] myMatrix_row = myMatrix[row];
139             while (c < ncols) {
140                 buffer.put(myMatrix_row[col] ? (byte) 1 : (byte) 0);
141                 ++c;
142                 ++col;
143             }
144             n += ncols;
145             ++r;
146             ++row;
147             c = 0;
148             col = myLowerCol;
149             ncols = Math.min(myColCount, buffer.remaining());
150         }
151         return n;
152     }
153 
154     /**
155      * {@inheritDoc}
156      *
157      * Receive as many items as possible from the given byte buffer to this
158      * buffer.
159      * <P>
160      * The <code>receiveItems()</code> method must not block the calling thread; if
161      * it does, all message I/O in MP will be blocked.
162      */
163     protected int receiveItems(int i,
164             int num,
165             ByteBuffer buffer) {
166         num = Math.min(num, buffer.remaining());
167         int n = 0;
168         int r = i2r(i);
169         int row = r + myLowerRow;
170         int c = i2c(i);
171         int col = c + myLowerCol;
172         int ncols = Math.min(myColCount - c, num);
173         while (r < myRowCount && ncols > 0) {
174             boolean[] myMatrix_row = myMatrix[row];
175             for (c = 0; c < ncols; ++c) {
176                 myMatrix_row[col] = buffer.get() != 0;
177                 ++col;
178             }
179             num -= ncols;
180             n += ncols;
181             ++r;
182             ++row;
183             col = myLowerCol;
184             ncols = Math.min(myColCount, num);
185         }
186         return n;
187     }
188 
189 }