1 //****************************************************************************** 2 // 3 // File: Unsigned8BitIntegerMatrixBuf.java 4 // Package: edu.rit.mp.buf 5 // Unit: Class edu.rit.mp.buf.Unsigned8BitIntegerMatrixBuf 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 java.nio.ByteBuffer; 43 44 import edu.rit.mp.Buf; 45 import edu.rit.mp.Unsigned8BitIntegerBuf; 46 import edu.rit.pj.reduction.IntegerOp; 47 import edu.rit.pj.reduction.Op; 48 import edu.rit.util.Arrays; 49 import edu.rit.util.Range; 50 51 /** 52 * Class Unsigned8BitIntegerMatrixBuf provides a buffer for a matrix of unsigned 53 * 8-bit integer items sent or received using the Message Protocol (MP). The 54 * matrix row and column strides may be 1 or greater than 1. While an instance 55 * of class Unsigned8BitIntegerMatrixBuf may be constructed directly, normally 56 * you will use a factory method in class {@linkplain 57 * edu.rit.mp.Unsigned8BitIntegerBuf Unsigned8BitIntegerBuf}. See that class for 58 * further information. 59 * 60 * @author Alan Kaminsky 61 * @version 05-Apr-2009 62 */ 63 public class Unsigned8BitIntegerMatrixBuf 64 extends Unsigned8BitIntegerBuf { 65 66 // Hidden data members. 67 int[][] myMatrix; 68 Range myRowRange; 69 Range myColRange; 70 int myLowerRow; 71 int myRowCount; 72 int myRowStride; 73 int myLowerCol; 74 int myColCount; 75 int myColStride; 76 77 // Exported constructors. 78 /** 79 * Construct a new unsigned 8-bit integer matrix buffer. It is assumed that 80 * the rows and columns of <code>theMatrix</code> are allocated and that each 81 * row of <code>theMatrix</code> has the same number of columns. 82 * 83 * @param theMatrix Matrix. 84 * @param theRowRange Range of rows to include. 85 * @param theColRange Range of columns to include. 86 */ 87 public Unsigned8BitIntegerMatrixBuf(int[][] theMatrix, 88 Range theRowRange, 89 Range theColRange) { 90 super(theRowRange.length() * theColRange.length()); 91 myMatrix = theMatrix; 92 myRowRange = theRowRange; 93 myColRange = theColRange; 94 myLowerRow = theRowRange.lb(); 95 myRowCount = theRowRange.length(); 96 myRowStride = theRowRange.stride(); 97 myLowerCol = theColRange.lb(); 98 myColCount = theColRange.length(); 99 myColStride = theColRange.stride(); 100 } 101 102 // Exported operations. 103 /** 104 * {@inheritDoc} 105 * 106 * Obtain the given item from this buffer. 107 * <P> 108 * The <code>get()</code> method must not block the calling thread; if it does, 109 * all message I/O in MP will be blocked. 110 */ 111 public int get(int i) { 112 return myMatrix[i2r(i) * myRowStride + myLowerRow][i2c(i) * myColStride + myLowerCol]; 113 } 114 115 /** 116 * {@inheritDoc} 117 * 118 * Store the given item in this buffer. 119 * <P> 120 * The <code>put()</code> method must not block the calling thread; if it does, 121 * all message I/O in MP will be blocked. 122 */ 123 public void put(int i, 124 int item) { 125 myMatrix[i2r(i) * myRowStride + myLowerRow][i2c(i) * myColStride + myLowerCol] = item; 126 } 127 128 /** 129 * {@inheritDoc} 130 * 131 * Copy items from the given buffer to this buffer. The number of items 132 * copied is this buffer's length or <code>theSrc</code>'s length, whichever is 133 * smaller. If <code>theSrc</code> is this buffer, the <code>copy()</code> method 134 * does nothing. 135 * @exception ClassCastException (unchecked exception) Thrown if 136 * <code>theSrc</code>'s item data type is not the same as this buffer's item 137 * data type. 138 */ 139 public void copy(Buf theSrc) { 140 if (theSrc == this) { 141 } else if (theSrc instanceof Unsigned8BitIntegerMatrixBuf) { 142 Unsigned8BitIntegerMatrixBuf src 143 = (Unsigned8BitIntegerMatrixBuf) theSrc; 144 Arrays.copy(src.myMatrix, src.myRowRange, src.myColRange, 145 this.myMatrix, this.myRowRange, this.myColRange); 146 } else { 147 Unsigned8BitIntegerBuf.defaultCopy((Unsigned8BitIntegerBuf) theSrc, this); 148 } 149 } 150 151 /** 152 * {@inheritDoc} 153 * 154 * Create a buffer for performing parallel reduction using the given binary 155 * operation. The results of the reduction are placed into this buffer. 156 * @exception ClassCastException (unchecked exception) Thrown if this 157 * buffer's element data type and the given binary operation's argument data 158 * type are not the same. 159 */ 160 public Buf getReductionBuf(Op op) { 161 return new Unsigned8BitIntegerMatrixReductionBuf(myMatrix, myRowRange, myColRange, (IntegerOp) op); 162 } 163 164 // Hidden operations. 165 /** 166 * {@inheritDoc} 167 * 168 * Send as many items as possible from this buffer to the given byte buffer. 169 * <P> 170 * The <code>sendItems()</code> method must not block the calling thread; if it 171 * does, all message I/O in MP will be blocked. 172 */ 173 protected int sendItems(int i, 174 ByteBuffer buffer) { 175 int n = 0; 176 int r = i2r(i); 177 int row = r * myRowStride + myLowerRow; 178 int c = i2c(i); 179 int col = c * myColStride + myLowerCol; 180 int ncols = Math.min(myColCount - c, buffer.remaining()); 181 while (r < myRowCount && ncols > 0) { 182 int[] myMatrix_row = myMatrix[row]; 183 while (c < ncols) { 184 buffer.put((byte) myMatrix_row[col]); 185 ++c; 186 col += myColStride; 187 } 188 n += ncols; 189 ++r; 190 row += myRowStride; 191 c = 0; 192 col = myLowerCol; 193 ncols = Math.min(myColCount, buffer.remaining()); 194 } 195 return n; 196 } 197 198 /** 199 * {@inheritDoc} 200 * 201 * Receive as many items as possible from the given byte buffer to this 202 * buffer. 203 * <P> 204 * The <code>receiveItems()</code> method must not block the calling thread; if 205 * it does, all message I/O in MP will be blocked. 206 */ 207 protected int receiveItems(int i, 208 int num, 209 ByteBuffer buffer) { 210 num = Math.min(num, buffer.remaining()); 211 int n = 0; 212 int r = i2r(i); 213 int row = r * myRowStride + myLowerRow; 214 int c = i2c(i); 215 int col = c * myColStride + myLowerCol; 216 int ncols = Math.min(myColCount - c, num); 217 while (r < myRowCount && ncols > 0) { 218 int[] myMatrix_row = myMatrix[row]; 219 for (c = 0; c < ncols; ++c) { 220 myMatrix_row[col] = buffer.get() & 0xFF; 221 col += myColStride; 222 } 223 num -= ncols; 224 n += ncols; 225 ++r; 226 row += myRowStride; 227 col = myLowerCol; 228 ncols = Math.min(myColCount, num); 229 } 230 return n; 231 } 232 233 /** 234 * Convert the given buffer index to a row index. 235 */ 236 int i2r(int i) { 237 return myColCount == 0 ? i : i / myColCount; 238 } 239 240 /** 241 * Convert the given buffer index to a column index. 242 */ 243 int i2c(int i) { 244 return myColCount == 0 ? 0 : i % myColCount; 245 } 246 247 }