001    package net.sf.cpsolver.studentsct.heuristics.studentord;
002    
003    import java.util.ArrayList;
004    import java.util.Collections;
005    import java.util.List;
006    
007    import net.sf.cpsolver.ifs.util.DataProperties;
008    import net.sf.cpsolver.studentsct.model.Student;
009    
010    /**
011     * Return the given set of students in a random order, however, all real
012     * students before last-like students.
013     * 
014     * @version StudentSct 1.2 (Student Sectioning)<br>
015     *          Copyright (C) 2007 - 2010 Tomas Muller<br>
016     *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
017     *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
018     * <br>
019     *          This library is free software; you can redistribute it and/or modify
020     *          it under the terms of the GNU Lesser General Public License as
021     *          published by the Free Software Foundation; either version 3 of the
022     *          License, or (at your option) any later version. <br>
023     * <br>
024     *          This library is distributed in the hope that it will be useful, but
025     *          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. <br>
028     * <br>
029     *          You should have received a copy of the GNU Lesser General Public
030     *          License along with this library; if not see
031     *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
032     */
033    public class StudentRandomRealFirstOrder implements StudentOrder {
034    
035        public StudentRandomRealFirstOrder(DataProperties config) {
036        }
037    
038        public StudentRandomRealFirstOrder() {
039        }
040    
041        /**
042         * Return the given set of students in a random order, however, all real
043         * students before last-like ({@link Student#isDummy()} is true) students.
044         **/
045        @Override
046        public List<Student> order(List<Student> students) {
047            List<Student> real = new ArrayList<Student>(students.size());
048            List<Student> dummy = new ArrayList<Student>(students.size());
049            for (Student student : students) {
050                if (student.isDummy())
051                    dummy.add(student);
052                else
053                    real.add(student);
054            }
055            Collections.shuffle(dummy);
056            Collections.shuffle(real);
057            dummy.addAll(real);
058            return dummy;
059        }
060    
061    }