001 package net.sf.cpsolver.ifs.example.jobshop;
002
003 import java.util.*;
004
005 import net.sf.cpsolver.ifs.model.*;
006
007 /**
008 * Job constraint.
009 * <br><br>
010 * Each job contians a given set of operations (variables).
011 * A job constraint is satisfied, if all operations of the job do not overlap in time and are processed in the given order.
012 *
013 * @version
014 * IFS 1.1 (Iterative Forward Search)<br>
015 * Copyright (C) 2006 Tomáš Müller<br>
016 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
017 * Lazenska 391, 76314 Zlin, Czech Republic<br>
018 * <br>
019 * This library is free software; you can redistribute it and/or
020 * modify it under the terms of the GNU Lesser General Public
021 * License as published by the Free Software Foundation; either
022 * version 2.1 of the License, or (at your option) any later version.
023 * <br><br>
024 * This library is distributed in the hope that it will be useful,
025 * but WITHOUT ANY WARRANTY; without even the implied warranty of
026 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
027 * Lesser General Public License for more details.
028 * <br><br>
029 * You should have received a copy of the GNU Lesser General Public
030 * License along with this library; if not, write to the Free Software
031 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
032 */
033 public class Job extends Constraint {
034 private int iJobNumber = 0;
035 private int iDueTime = -1;
036
037 /**
038 * Constructor
039 * @param jobNumber job number
040 */
041 public Job(int jobNumber) {
042 super();
043 iJobNumber = jobNumber;
044 }
045
046 /**
047 * Set due time
048 */
049 public void setDueTime(int dueTime) { iDueTime = dueTime; }
050
051 /**
052 * Get due time
053 */
054 public int getDueTime() { return iDueTime; }
055
056 /**
057 * Get job number
058 */
059 public int getJobNumner() { return iJobNumber; }
060
061 /**
062 * Count job operations for the job (i.e., the number of variables in this constraint)
063 */
064 public int countOperations() { return variables().size(); }
065
066 /**
067 * Get operation of the given index (0..countOperations()-1)
068 */
069 public Operation getOperation(int opNumber) { return (Operation)variables().get(opNumber); }
070
071 /**
072 * Adds conflicting operations into the set of conflicts.
073 */
074 public void computeConflicts(Value value, Set conflicts) {
075 Location location = (Location)value;
076 Operation operation = (Operation)value.variable();
077 for (Enumeration e=assignedVariables().elements();e.hasMoreElements();) {
078 Operation o = (Operation)e.nextElement();
079 if (o.getOperationNumber()==operation.getOperationNumber()) continue;
080 Location l = (Location)o.getAssignment();
081 if (o.getOperationNumber()<operation.getOperationNumber()) {
082 if (!l.before(location)) conflicts.add(l);
083 } else {
084 if (!l.after(location)) conflicts.add(l);
085 }
086 }
087 }
088
089 /**
090 * True if there is an operation from the same job which violates with the given assignment.
091 */
092 public boolean inConflict(Value value) {
093 Location location = (Location)value;
094 Operation operation = (Operation)value.variable();
095 for (Enumeration e=assignedVariables().elements();e.hasMoreElements();) {
096 Operation o = (Operation)e.nextElement();
097 if (o.getOperationNumber()==operation.getOperationNumber()) continue;
098 Location l = (Location)o.getAssignment();
099 if (o.getOperationNumber()<operation.getOperationNumber()) {
100 if (!l.before(location)) return true;
101 } else {
102 if (!l.after(location)) return true;
103 }
104 }
105 return false;
106 }
107
108 /**
109 * True if the two assignments (placement of opeartions of the same job in time) violates each other.
110 */
111 public boolean isConsistent(Value value1, Value value2) {
112 Location location1 = (Location)value1;
113 Operation operation1 = (Operation)value1.variable();
114 Location location2 = (Location)value2;
115 Operation operation2 = (Operation)value2.variable();
116 if (operation1.getOperationNumber()<operation2.getOperationNumber()) {
117 if (location1.before(location2)) return true;
118 } else {
119 if (location2.before(location1)) return true;
120 }
121 return false;
122 }
123
124 /**
125 * String representation -- for debuging and printing purposes
126 */
127 public String toString() { return "J"+iJobNumber; }
128 /**
129 * Name of the job (e.g. J10 where 10 is the job number)
130 */
131 public String getName() { return "J"+iJobNumber; }
132 }