001package net.sf.cpsolver.ifs.example.jobshop;
002
003import java.io.BufferedReader;
004import java.io.FileReader;
005import java.io.FileWriter;
006import java.io.IOException;
007import java.io.PrintWriter;
008import java.util.ArrayList;
009import java.util.Collections;
010import java.util.Comparator;
011import java.util.List;
012import java.util.Map;
013import java.util.StringTokenizer;
014
015import net.sf.cpsolver.ifs.model.Model;
016import net.sf.cpsolver.ifs.util.ToolBox;
017
018/**
019 * Job Shop model. <br>
020 * <br>
021 * It contains the number of available time slots and all machines and jobs. <br>
022 * <br>
023 * It can also load the model from a file and save the solution. <br>
024 * <br>
025 * <b>Input file format:</b>
026 * <ul>
027 * First line:
028 * <ul>
029 * <code>&lt;number of jobs&gt; &lt;number of machines&gt;</code>
030 * </ul>
031 * Following lines:
032 * <ul>
033 * space separated list (a line for each job) of operations, each operation
034 * consist of machine number and operation processing time
035 * </ul>
036 * Example of 10 jobs, 10 machines:
037 * <ul>
038 * <code>
039 * 10 10<br>
040 * 4 88 8 68 6 94 5 99 1 67 2 89 9 77 7 99 0 86 3 92<br>
041 * 5 72 3 50 6 69 4 75 2 94 8 66 0 92 1 82 7 94 9 63<br>
042 * 9 83 8 61 0 83 1 65 6 64 5 85 7 78 4 85 2 55 3 77<br>
043 * 7 94 2 68 1 61 4 99 3 54 6 75 5 66 0 76 9 63 8 67<br>
044 * 3 69 4 88 9 82 8 95 0 99 2 67 6 95 5 68 7 67 1 86<br>
045 * 1 99 4 81 5 64 6 66 8 80 2 80 7 69 9 62 3 79 0 88<br>
046 * 7 50 1 86 4 97 3 96 0 95 8 97 2 66 5 99 6 52 9 71<br>
047 * 4 98 6 73 3 82 2 51 1 71 5 94 7 85 0 62 8 95 9 79<br>
048 * 0 94 6 71 3 81 7 85 1 66 2 90 4 76 5 58 8 93 9 97<br>
049 * 3 50 0 59 1 82 8 67 7 56 9 96 6 58 4 81 5 59 2 96<br>
050 * </code>
051 * </ul>
052 * For instance, the first job is described as follows:
053 * <ul>
054 * 88 time units on machine 4, then 68 time units on machine 8, then 94 time
055 * units on machine 6 ...
056 * </ul>
057 * </ul><br>
058 * <b>Output file firmat:</b>
059 * <ul>
060 * A line for each machine, in each line there is a space separated list of jobs
061 * which the machine will process in the order they will be processed.
062 * </ul>
063 * 
064 * @version IFS 1.2 (Iterative Forward Search)<br>
065 *          Copyright (C) 2006 - 2010 Tomáš Müller<br>
066 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
067 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
068 * <br>
069 *          This library is free software; you can redistribute it and/or modify
070 *          it under the terms of the GNU Lesser General Public License as
071 *          published by the Free Software Foundation; either version 3 of the
072 *          License, or (at your option) any later version. <br>
073 * <br>
074 *          This library is distributed in the hope that it will be useful, but
075 *          WITHOUT ANY WARRANTY; without even the implied warranty of
076 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
077 *          Lesser General Public License for more details. <br>
078 * <br>
079 *          You should have received a copy of the GNU Lesser General Public
080 *          License along with this library; if not see
081 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
082 */
083public class JobShopModel extends Model<Operation, Location> {
084    private int iTotalNumberOfSlots = 1250;
085    private Machine[] iMachines;
086    private Job[] iJobs;
087
088    /**
089     * Constructor ???
090     * 
091     * @param nrMachines
092     *            number of machines
093     * @param nrJobs
094     *            number of jobs
095     */
096    public JobShopModel(int nrMachines, int nrJobs) {
097        super();
098        iMachines = new Machine[nrMachines];
099        iJobs = new Job[nrJobs];
100    }
101
102    /** Get total number of slots */
103    public int getTotalNumberOfSlots() {
104        return iTotalNumberOfSlots;
105    }
106
107    /** Get machine of the given numbner */
108    public Machine getMachine(int machineNumber) {
109        return iMachines[machineNumber];
110    }
111
112    /** Count number of machines in the model */
113    public int countMachines() {
114        return iMachines.length;
115    }
116
117    /** Get job of the given number */
118    public Job getJob(int jobNumber) {
119        return iJobs[jobNumber];
120    }
121
122    /** Count number of jobs in the model */
123    public int countJobs() {
124        return iJobs.length;
125    }
126
127    private void setJob(int jobNumber, Job job) {
128        iJobs[jobNumber] = job;
129    }
130
131    private void setMachine(int machineNumber, Machine machine) {
132        iMachines[machineNumber] = machine;
133    }
134
135    /** Loads the model from the given file */
136    public static JobShopModel loadModel(String file) throws IOException {
137        BufferedReader reader = new BufferedReader(new FileReader(file));
138        String line = reader.readLine();
139        while (line.startsWith("#"))
140            line = reader.readLine();
141        StringTokenizer stk = new StringTokenizer(line, " ");
142        int nrJobs = Integer.parseInt(stk.nextToken());
143        int nrMachines = Integer.parseInt(stk.nextToken());
144        JobShopModel model = new JobShopModel(nrMachines, nrJobs);
145        Machine[] machine = new Machine[nrMachines];
146        for (int i = 0; i < nrMachines; i++) {
147            machine[i] = new Machine(i);
148            model.addConstraint(machine[i]);
149            model.setMachine(i, machine[i]);
150        }
151        for (int i = 0; i < nrJobs; i++) {
152            Job job = new Job(i);
153            model.addConstraint(job);
154            model.setJob(i, job);
155            line = reader.readLine();
156            stk = new StringTokenizer(line, " ");
157            for (int j = 0; j < nrMachines; j++) {
158                int machineNumber = Integer.parseInt(stk.nextToken());
159                int processingTime = Integer.parseInt(stk.nextToken());
160                Operation operation = new Operation(job, machine[machineNumber], j, processingTime);
161                model.addVariable(operation);
162                job.addVariable(operation);
163                machine[machineNumber].addVariable(operation);
164            }
165            if (stk.hasMoreTokens()) {
166                job.setDueTime(Integer.parseInt(stk.nextToken()));
167            }
168        }
169        reader.close();
170        for (Operation o : model.variables())
171            o.init();
172        return model;
173    }
174
175    /** Get finishing time of the current (partial) solution */
176    public int getFinishingTime() {
177        int ret = 0;
178        for (Operation op : assignedVariables()) {
179            ret = Math.max(ret, op.getAssignment().getFinishingTime());
180        }
181        return ret;
182    }
183
184    /** Get information table */
185    @Override
186    public Map<String, String> getInfo() {
187        Map<String, String> ret = super.getInfo();
188        ret.put("Finishing time", String.valueOf(getFinishingTime()));
189        return ret;
190    }
191
192    /** Save the solution into the given file */
193    public void save(String file) throws java.io.IOException {
194        PrintWriter writer = new PrintWriter(new FileWriter(file));
195        for (int i = 0; i < countMachines(); i++) {
196            Machine m = getMachine(i);
197            List<Operation> ops = new ArrayList<Operation>(m.variables());
198            Collections.sort(ops, new OperationComparator());
199            for (Operation var : ops) {
200                Operation op = var;
201                if (op.getAssignment() != null)
202                    writer.print((op.getJobNumber() < 10 ? " " : "") + op.getJobNumber() + " ");
203            }
204            writer.println();
205        }
206        writer.println(";");
207        Map<String, String> info = getInfo();
208        for (String key : info.keySet()) {
209            String value = info.get(key);
210            writer.println("; " + key + ": " + value);
211        }
212        writer.println(";");
213        for (int i = 0; i < countJobs(); i++) {
214            Job job = getJob(i);
215            writer.print("; ");
216            for (Operation op : job.variables()) {
217                Location loc = op.getAssignment();
218                writer.print((loc == null ? "----" : ToolBox.trim(String.valueOf(loc.getStartTime()), 4)) + " ");
219            }
220            writer.println();
221        }
222        writer.flush();
223        writer.close();
224    }
225
226    private static class OperationComparator implements Comparator<Operation> {
227        @Override
228        public int compare(Operation op1, Operation op2) {
229            Location loc1 = op1.getAssignment();
230            Location loc2 = op2.getAssignment();
231            if (loc1 == null) {
232                if (loc2 == null)
233                    return 0;
234                else
235                    return -1;
236            }
237            if (loc2 == null)
238                return 1;
239            return (loc1.getStartTime() < loc2.getStartTime() ? -1 : loc1.getStartTime() == loc2.getStartTime() ? 0 : 1);
240        }
241    }
242}