1 | import java.io.*;
|
---|
2 | import java.util.ArrayList;
|
---|
3 | import java.util.List;
|
---|
4 | import java.util.concurrent.Semaphore;
|
---|
5 |
|
---|
6 | /**
|
---|
7 | * @author Riste Stojanov
|
---|
8 | */
|
---|
9 |
|
---|
10 | class FileScanner extends Thread {
|
---|
11 |
|
---|
12 | static final List<File> matrixFiles = new ArrayList<>();
|
---|
13 | private final File directoryToScan;
|
---|
14 |
|
---|
15 | FileScanner(File directoryToScan) {
|
---|
16 | this.directoryToScan = directoryToScan;
|
---|
17 | }
|
---|
18 |
|
---|
19 | @Override
|
---|
20 | public void run() {
|
---|
21 | try {
|
---|
22 | List<FileScanner> scanners = new ArrayList<>();
|
---|
23 | File[] files = directoryToScan.listFiles();
|
---|
24 | for (File file : files) {
|
---|
25 |
|
---|
26 | if (file.isFile() &&
|
---|
27 | file.getName().endsWith(".mat")) {
|
---|
28 | synchronized (matrixFiles) {
|
---|
29 | matrixFiles.add(file);
|
---|
30 | }
|
---|
31 | }
|
---|
32 | if (file.isDirectory()) {
|
---|
33 | FileScanner fs = new FileScanner(file);
|
---|
34 | scanners.add(fs);
|
---|
35 | fs.start();
|
---|
36 | }
|
---|
37 |
|
---|
38 | }
|
---|
39 | for (FileScanner scanner : scanners) {
|
---|
40 | scanner.join();
|
---|
41 | }
|
---|
42 | System.out.println("Done scanning: " + directoryToScan.getAbsolutePath());
|
---|
43 | } catch (Exception e) {
|
---|
44 | e.printStackTrace();
|
---|
45 | }
|
---|
46 | }
|
---|
47 | }
|
---|
48 |
|
---|
49 | class Reader extends Thread {
|
---|
50 | private final String matrixFile;
|
---|
51 | int[][] matrix;
|
---|
52 |
|
---|
53 | Reader(String matrixFile) {
|
---|
54 | this.matrixFile = matrixFile;
|
---|
55 | }
|
---|
56 |
|
---|
57 | /**
|
---|
58 | * This method should execute in background
|
---|
59 | */
|
---|
60 | @Override
|
---|
61 | public void run() {
|
---|
62 | // todo: complete this method according to the text description
|
---|
63 | // todo: The variable in should provide the readInt() method
|
---|
64 | try (DataInputStream s = new DataInputStream(new FileInputStream(new File(matrixFile)))) {
|
---|
65 |
|
---|
66 | int n = s.readInt();
|
---|
67 | this.matrix = new int[n][n];
|
---|
68 | for (int i = 0; i < n; i++) {
|
---|
69 | for (int j = 0; j < n; j++) {
|
---|
70 | matrix[i][j] = s.readInt();
|
---|
71 | System.out.print(matrix[i][j] + " ");
|
---|
72 | }
|
---|
73 | System.out.println();
|
---|
74 | }
|
---|
75 | } catch (Exception e) {
|
---|
76 | e.printStackTrace();
|
---|
77 | }
|
---|
78 | }
|
---|
79 | }
|
---|
80 |
|
---|
81 | class Writer extends Thread {
|
---|
82 |
|
---|
83 | private final String outputPath;
|
---|
84 | private final int[][] matrix;
|
---|
85 |
|
---|
86 | Writer(String outputPath, int[][] matrix) {
|
---|
87 | this.outputPath = outputPath;
|
---|
88 | this.matrix = matrix;
|
---|
89 | }
|
---|
90 |
|
---|
91 |
|
---|
92 | @Override
|
---|
93 | public void run() {
|
---|
94 | int n = matrix.length;
|
---|
95 | try (DataOutputStream dos = new DataOutputStream(new FileOutputStream(outputPath))) {
|
---|
96 | dos.writeInt(n);
|
---|
97 | for (int i = 0; i < n; i++) {
|
---|
98 | for (int j = 0; j < n; j++) {
|
---|
99 | // todo: write the element
|
---|
100 | System.out.print(matrix[i][j] + " ");
|
---|
101 | dos.writeInt(matrix[i][j]);
|
---|
102 | }
|
---|
103 | System.out.println();
|
---|
104 | }
|
---|
105 |
|
---|
106 | } catch (Exception e) {
|
---|
107 | e.printStackTrace();
|
---|
108 | }
|
---|
109 | }
|
---|
110 | }
|
---|
111 |
|
---|
112 | class Transformer extends Thread {
|
---|
113 | final int row;
|
---|
114 | final int column;
|
---|
115 | private final int[][] matrix;
|
---|
116 | int result;
|
---|
117 |
|
---|
118 | Transformer(int[][] matrix, int row, int column) {
|
---|
119 | this.matrix = matrix;
|
---|
120 | this.row = row;
|
---|
121 | this.column = column;
|
---|
122 | }
|
---|
123 |
|
---|
124 | @Override
|
---|
125 | public void run() {
|
---|
126 | try {
|
---|
127 | // todo: allow maximum 10 parallel executions
|
---|
128 | MatrixMultiplication.semaphore.acquire();
|
---|
129 | int n = matrix.length;
|
---|
130 | for (int k = 0; k < n; k++) {
|
---|
131 | result += matrix[row][k] * matrix[k][column];
|
---|
132 | }
|
---|
133 | MatrixMultiplication.semaphore.release();
|
---|
134 | System.out.print(".");
|
---|
135 | MatrixMultiplication.barrier.release();
|
---|
136 | } catch (Exception e) {
|
---|
137 | e.printStackTrace();
|
---|
138 | }
|
---|
139 | }
|
---|
140 | }
|
---|
141 |
|
---|
142 | public class MatrixMultiplication {
|
---|
143 |
|
---|
144 | static Semaphore barrier = new Semaphore(0);
|
---|
145 | static Semaphore semaphore = new Semaphore(10);
|
---|
146 |
|
---|
147 | public static void main1(String[] args) {
|
---|
148 | int n = 30;
|
---|
149 | int[][] matrix = new int[n][n];
|
---|
150 | for (int i = 0; i < n; i++) {
|
---|
151 | for (int j = 0; j < n; j++) {
|
---|
152 | matrix[i][j] = 1;
|
---|
153 | }
|
---|
154 | }
|
---|
155 | Writer w = new Writer("data/matrix.mat", matrix);
|
---|
156 | w.run();
|
---|
157 | System.out.println("\n==============================================================================================");
|
---|
158 | Reader r = new Reader("data/matrix.mat");
|
---|
159 | r.run();
|
---|
160 | }
|
---|
161 |
|
---|
162 |
|
---|
163 | public static void main(String[] args) throws FileNotFoundException, InterruptedException {
|
---|
164 | List<Transformer> transformers = new ArrayList<>();
|
---|
165 |
|
---|
166 | Reader reader = new Reader("data/matrix.mat");
|
---|
167 | // todo: execute file reading in background
|
---|
168 | reader.start();
|
---|
169 |
|
---|
170 | // todo: wait for the matrix to be read
|
---|
171 | reader.join();
|
---|
172 |
|
---|
173 | // todo: transform the matrix
|
---|
174 | int n = reader.matrix.length;
|
---|
175 |
|
---|
176 | for (int i = 0; i < n; i++) {
|
---|
177 | for (int j = 0; j < n; j++) {
|
---|
178 | Transformer t = new Transformer(reader.matrix, i, j);
|
---|
179 | transformers.add(t);
|
---|
180 | // todo: start the background execution
|
---|
181 | t.start();
|
---|
182 | }
|
---|
183 | }
|
---|
184 |
|
---|
185 |
|
---|
186 | // todo: wait for all transformers to finish
|
---|
187 | barrier.acquire(n * n);
|
---|
188 |
|
---|
189 | System.out.println("==============================================================================================");
|
---|
190 | int[][] result = new int[n][n];
|
---|
191 | for (Transformer t : transformers) {
|
---|
192 | result[t.row][t.column] = t.result;
|
---|
193 | }
|
---|
194 |
|
---|
195 | Writer writer = new Writer("data/out.bin", result);
|
---|
196 | // todo: execute file writing in background
|
---|
197 | writer.start();
|
---|
198 |
|
---|
199 | FileScanner scanner = new FileScanner(new File("data"));
|
---|
200 | // todo: execute file scanning in background
|
---|
201 | scanner.start();
|
---|
202 | // todo: wait for the scanner to finish and show the results
|
---|
203 | scanner.join();
|
---|
204 | for (File matrixFile : scanner.matrixFiles) {
|
---|
205 | // System.out.println(matrixFile.getAbsolutePath());
|
---|
206 | }
|
---|
207 |
|
---|
208 | }
|
---|
209 |
|
---|
210 |
|
---|
211 | } |
---|