    001package org.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 org.cpsolver.ifs.assignment.Assignment;
    016import org.cpsolver.ifs.model.Model;
    017import org.cpsolver.ifs.util.ToolBox;
    018
    019
    020/**
    021 * Job Shop model. <br>
    022 * <br>
    023 * It contains the number of available time slots and all machines and jobs. <br>
    024 * <br>
    025 * It can also load the model from a file and save the solution. <br>
    026 * <br>
    027 * <b>Input file format:</b>
    028 * First line:
    029 * <pre><code>&lt;number of jobs&gt; &lt;number of machines&gt;</code></pre>
    030 * Following lines:
    031 * <pre>
    032 * space separated list (a line for each job) of operations, each operation
    033 * consist of machine number and operation processing time
    034 * </pre>
    035 * Example of 10 jobs, 10 machines:
    036 * <pre><code>
    037 * 10 10
    038 * 4 88 8 68 6 94 5 99 1 67 2 89 9 77 7 99 0 86 3 92
    039 * 5 72 3 50 6 69 4 75 2 94 8 66 0 92 1 82 7 94 9 63
    040 * 9 83 8 61 0 83 1 65 6 64 5 85 7 78 4 85 2 55 3 77
    041 * 7 94 2 68 1 61 4 99 3 54 6 75 5 66 0 76 9 63 8 67
    042 * 3 69 4 88 9 82 8 95 0 99 2 67 6 95 5 68 7 67 1 86
    043 * 1 99 4 81 5 64 6 66 8 80 2 80 7 69 9 62 3 79 0 88
    044 * 7 50 1 86 4 97 3 96 0 95 8 97 2 66 5 99 6 52 9 71
    045 * 4 98 6 73 3 82 2 51 1 71 5 94 7 85 0 62 8 95 9 79
    046 * 0 94 6 71 3 81 7 85 1 66 2 90 4 76 5 58 8 93 9 97
    047 * 3 50 0 59 1 82 8 67 7 56 9 96 6 58 4 81 5 59 2 96
    048 * </code></pre>
    049 * For instance, the first job is described as follows:
    050 * <pre>
    051 * 88 time units on machine 4, then 68 time units on machine 8, then 94 time
    052 * units on machine 6 ...
    053 * </pre>
    054 * <br>
    055 * <b>Output file firmat:</b>
    056 * <pre>
    057 * A line for each machine, in each line there is a space separated list of jobs
    058 * which the machine will process in the order they will be processed.
    059 * </pre>
    060 *
    061 * @author  Tomáš Müller
    062 * @version IFS 1.3 (Iterative Forward Search)<br>
    063 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    064 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    065 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    066 * <br>
    067 *          This library is free software; you can redistribute it and/or modify
    068 *          it under the terms of the GNU Lesser General Public License as
    069 *          published by the Free Software Foundation; either version 3 of the
    070 *          License, or (at your option) any later version. <br>
    071 * <br>
    072 *          This library is distributed in the hope that it will be useful, but
    073 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    074 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    075 *          Lesser General Public License for more details. <br>
    076 * <br>
    077 *          You should have received a copy of the GNU Lesser General Public
    078 *          License along with this library; if not see
    079 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    080 */
    081public class JobShopModel extends Model<Operation, Location> {
    082    private int iTotalNumberOfSlots = 1250;
    083    private Machine[] iMachines;
    084    private Job[] iJobs;
    085
    086    /**
    087     * Constructor �
    088     *
    089     * @param nrMachines
    090     *            number of machines
    091     * @param nrJobs
    092     *            number of jobs
    093     */
    094    public JobShopModel(int nrMachines, int nrJobs) {
    095        super();
    096        iMachines = new Machine[nrMachines];
    097        iJobs = new Job[nrJobs];
    098    }
    099
    100    /** Get total number of slots
    101     * @return total number of slots
    102     **/
    103    public int getTotalNumberOfSlots() {
    104        return iTotalNumberOfSlots;
    105    }
    106
    107    /** Get machine of the given number
    108     * @param machineNumber machine number
    109     * @return machine of the given number
    110     **/
    111    public Machine getMachine(int machineNumber) {
    112        return iMachines[machineNumber];
    113    }
    114
    115    /** Count number of machines in the model
    116     * @return number of machines in the model
    117     **/
    118    public int countMachines() {
    119        return iMachines.length;
    120    }
    121
    122    /** Get job of the given number
    123     * @param jobNumber job number
    124     * @return job of the given number
    125     **/
    126    public Job getJob(int jobNumber) {
    127        return iJobs[jobNumber];
    128    }
    129
    130    /** Count number of jobs in the model
    131     * @return number of jobs in the model
    132     **/
    133    public int countJobs() {
    134        return iJobs.length;
    135    }
    136
    137    private void setJob(int jobNumber, Job job) {
    138        iJobs[jobNumber] = job;
    139    }
    140
    141    private void setMachine(int machineNumber, Machine machine) {
    142        iMachines[machineNumber] = machine;
    143    }
    144
    145    /** Loads the model from the given file
    146     * @param file file to load
    147     * @return loaded model
    148     * @throws IOException thrown when there is a problem reading the input file */
    149    public static JobShopModel loadModel(String file) throws IOException {
    150        BufferedReader reader = new BufferedReader(new FileReader(file));
    151        String line = reader.readLine();
    152        while (line.startsWith("#"))
    153            line = reader.readLine();
    154        StringTokenizer stk = new StringTokenizer(line, " ");
    155        int nrJobs = Integer.parseInt(stk.nextToken());
    156        int nrMachines = Integer.parseInt(stk.nextToken());
    157        JobShopModel model = new JobShopModel(nrMachines, nrJobs);
    158        Machine[] machine = new Machine[nrMachines];
    159        for (int i = 0; i < nrMachines; i++) {
    160            machine[i] = new Machine(i);
    161            model.addConstraint(machine[i]);
    162            model.setMachine(i, machine[i]);
    163        }
    164        for (int i = 0; i < nrJobs; i++) {
    165            Job job = new Job(i);
    166            model.addConstraint(job);
    167            model.setJob(i, job);
    168            line = reader.readLine();
    169            stk = new StringTokenizer(line, " ");
    170            for (int j = 0; j < nrMachines; j++) {
    171                int machineNumber = Integer.parseInt(stk.nextToken());
    172                int processingTime = Integer.parseInt(stk.nextToken());
    173                Operation operation = new Operation(job, machine[machineNumber], j, processingTime);
    174                model.addVariable(operation);
    175                job.addVariable(operation);
    176                machine[machineNumber].addVariable(operation);
    177            }
    178            if (stk.hasMoreTokens()) {
    179                job.setDueTime(Integer.parseInt(stk.nextToken()));
    180            }
    181        }
    182        reader.close();
    183        for (Operation o : model.variables())
    184            o.init();
    185        return model;
    186    }
    187
    188    /** Get finishing time of the current (partial) solution
    189     * @param assignment current assignment
    190     * @return finishing time of the current (partial) solution
    191     **/
    192    public int getFinishingTime(Assignment<Operation, Location> assignment) {
    193        int ret = 0;
    194        for (Operation op : assignment.assignedVariables()) {
    195            ret = Math.max(ret, assignment.getValue(op).getFinishingTime());
    196        }
    197        return ret;
    198    }
    199
    200    /** Get information table */
    201    @Override
    202    public Map<String, String> getInfo(Assignment<Operation, Location> assignment) {
    203        Map<String, String> ret = super.getInfo(assignment);
    204        ret.put("Finishing time", String.valueOf(getFinishingTime(assignment)));
    205        return ret;
    206    }
    207
    208    /** Save the solution into the given file
    209     * @param assignment current assignment
    210     * @param file file to write
    211     * @throws java.io.IOException throw when there is a problem writing the file
    212     **/
    213    public void save(Assignment<Operation, Location> assignment, String file) throws java.io.IOException {
    214        PrintWriter writer = new PrintWriter(new FileWriter(file));
    215        for (int i = 0; i < countMachines(); i++) {
    216            Machine m = getMachine(i);
    217            List<Operation> ops = new ArrayList<Operation>(m.variables());
    218            Collections.sort(ops, new OperationComparator(assignment));
    219            for (Operation var : ops) {
    220                Operation op = var;
    221                if (assignment.getValue(op) != null)
    222                    writer.print((op.getJobNumber() < 10 ? " " : "") + op.getJobNumber() + " ");
    223            }
    224            writer.println();
    225        }
    226        writer.println(";");
    227        Map<String, String> info = getInfo(assignment);
    228        for (String key : info.keySet()) {
    229            String value = info.get(key);
    230            writer.println("; " + key + ": " + value);
    231        }
    232        writer.println(";");
    233        for (int i = 0; i < countJobs(); i++) {
    234            Job job = getJob(i);
    235            writer.print("; ");
    236            for (Operation op : job.variables()) {
    237                Location loc = assignment.getValue(op);
    238                writer.print((loc == null ? "----" : ToolBox.trim(String.valueOf(loc.getStartTime()), 4)) + " ");
    239            }
    240            writer.println();
    241        }
    242        writer.flush();
    243        writer.close();
    244    }
    245
    246    private static class OperationComparator implements Comparator<Operation> {
    247        Assignment<Operation, Location> iAssignment;
    248
    249        public OperationComparator(Assignment<Operation, Location> assignment) {
    250            iAssignment = assignment;
    251        }
    252
    253        @Override
    254        public int compare(Operation op1, Operation op2) {
    255            Location loc1 = iAssignment.getValue(op1);
    256            Location loc2 = iAssignment.getValue(op2);
    257            if (loc1 == null) {
    258                if (loc2 == null)
    259                    return 0;
    260                else
    261                    return -1;
    262            }
    263            if (loc2 == null)
    264                return 1;
    265            return (loc1.getStartTime() < loc2.getStartTime() ? -1 : loc1.getStartTime() == loc2.getStartTime() ? 0 : 1);
    266        }
    267    }
    268}