JenrlConstraint (Constraint Solver API Documentation -- CPSolver v1.2 build 156)

java.lang.Object
- net.sf.cpsolver.ifs.model.Constraint<V,T>
- - net.sf.cpsolver.ifs.model.BinaryConstraint<Lecture,Placement>
  - - net.sf.cpsolver.coursett.constraint.JenrlConstraint

All Implemented Interfaces:

Comparable<Constraint<Lecture,Placement>>, WeakeningConstraint<Lecture,Placement>
```
public class JenrlConstraint
extends BinaryConstraint<Lecture,Placement>
implements WeakeningConstraint<Lecture,Placement>
```
Join student enrollment constraint.
This constraint is placed between all pairs of classes where there is at least one student attending both classes. It represents a number of student conflicts (number of joined enrollments), if the given two classes overlap in time.
Also, it dynamically maintains the counter of all student conflicts. It is a soft constraint.

Version:

CourseTT 1.2 (University Course Timetabling)
Copyright (C) 2006 - 2010 Tomáš Müller
muller@unitime.org
http://muller.unitime.org

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not see http://www.gnu.org/licenses/.

Field Summary
- Fields inherited from class net.sf.cpsolver.ifs.model.Constraint
  iAssignedVariables, iConstraintListeners, iId

Constructor Summary

Constructors
Constructor and Description

JenrlConstraint()
Constructor

Constructors
Constructor and Description
`JenrlConstraint()` Constructor

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addVariable(Lecture variable)` Add a variable to this constraint
`boolean`	`areStudentConflictsCommitted()`
`boolean`	`areStudentConflictsDistance()`
`boolean`	`areStudentConflictsDistance(Placement value)`
`boolean`	`areStudentConflictsHard()`
`void`	`assigned(long iteration, Placement value)` Given value is to be assigned to its varable.
`void`	`computeConflicts(Placement value, Set<Placement> conflicts)` The only method which has to be implemented by any constraint.
`void`	`decJenrl(Student student)` Decrement the number of joined enrollments (during student final sectioning)
`Set<Student>`	`getInstructors()`
`long`	`getJenrl()` Number of joined enrollments (during student final sectioning)
`double`	`getJenrlWeight(Student student)`
`String`	`getName()` Constraint's name -- for printing purposes
`int`	`getNrInstructors()`
`int`	`getNrStudents()`
`Set<Student>`	`getStudents()`
`void`	`incJenrl(Student student)` Increment the number of joined enrollments (during student final sectioning)
`boolean`	`inConflict(Placement value)` Returns true if the given assignment is inconsistent with the existing assignments respecting this constraint.
`boolean`	`isConsistent(Placement value1, Placement value2)` Returns true if the given assignments are consistent respecting this constraint.
`boolean`	`isHard()` Returns true if the constraint is hard.
`boolean`	`isInConflict()` True if the given two lectures overlap in time
`static boolean`	`isInConflict(Placement p1, Placement p2, DistanceMetric m)` Returns true if the given placements are overlapping or they are back-to-back and too far for students.
`boolean`	`isOfTheSameProblem()`
`boolean`	`isOverLimit()`
`boolean`	`isToBeIgnored()` Returns true if there is `IgnoreStudentConflictsConstraint` between the two lectures.
`double`	`jenrl()`
`long`	`jenrl(Lecture variable, Placement value)` Number of joined enrollments if the given value is assigned to the given variable
`double`	`priority()`
`String`	`toString()`
`void`	`unassigned(long iteration, Placement value)` Given value is unassigned from its variable.
`void`	`weaken()` Weaken the constraint.
`void`	`weaken(Placement value)` Weaken the constraint enough so that it can assign the given value.

Methods inherited from class net.sf.cpsolver.ifs.model.BinaryConstraint
another, first, isFirst, second

Methods inherited from class net.sf.cpsolver.ifs.model.Constraint
addConstraintListener, assignedVariables, compareTo, constraintListeners, countAssignedVariables, countVariables, equals, getDescription, getId, getModel, hashCode, removeConstraintListener, removeVariable, setModel, variables

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - JenrlConstraint
```
public JenrlConstraint()
```
    Constructor
- Method Detail
  - addVariable
```
public void addVariable(Lecture variable)
```
    Description copied from class: Constraint
    
    Add a variable to this constraint
    
    Overrides:
    
    addVariable in class BinaryConstraint<Lecture,Placement>
  - computeConflicts
```
public void computeConflicts(Placement value,
                             Set<Placement> conflicts)
```
    Description copied from class: Constraint
    
    The only method which has to be implemented by any constraint. It returns the values which needs to be unassigned in order to make this constraint consistent with the given value if it is assigned to its variable. The computed list of conflicting values is added to the given set of conflicts.
    
    Specified by:
    
    computeConflicts in class Constraint<Lecture,Placement>
    
    Parameters:
    
    value - value to be assigned to its varaible
    
    conflicts - resultant set of conflicting values
  - inConflict
```
public boolean inConflict(Placement value)
```
    Description copied from class: Constraint
    
    Returns true if the given assignment is inconsistent with the existing assignments respecting this constraint. This method is used by MAC (see MacPropagation).
    
    Overrides:
    
    inConflict in class Constraint<Lecture,Placement>
  - isConsistent
```
public boolean isConsistent(Placement value1,
                            Placement value2)
```
    Description copied from class: Constraint
    
    Returns true if the given assignments are consistent respecting this constraint. This method is used by MAC (see MacPropagation).
    
    Overrides:
    
    isConsistent in class Constraint<Lecture,Placement>
  - unassigned
```
public void unassigned(long iteration,
                       Placement value)
```
    Description copied from class: Constraint
    
    Given value is unassigned from its variable.
    
    Overrides:
    
    unassigned in class Constraint<Lecture,Placement>
  - isInConflict
```
public static boolean isInConflict(Placement p1,
                                   Placement p2,
                                   DistanceMetric m)
```
    Returns true if the given placements are overlapping or they are back-to-back and too far for students.
  - assigned
```
public void assigned(long iteration,
                     Placement value)
```
    Description copied from class: Constraint
    
    Given value is to be assigned to its varable. In this method, the constraint should unassigns all varaibles which are in conflict with the given assignment because of this constraint.
    
    Overrides:
    
    assigned in class Constraint<Lecture,Placement>
  - jenrl
```
public long jenrl(Lecture variable,
                  Placement value)
```
    Number of joined enrollments if the given value is assigned to the given variable
  - isInConflict
```
public boolean isInConflict()
```
    True if the given two lectures overlap in time
  - incJenrl
```
public void incJenrl(Student student)
```
    Increment the number of joined enrollments (during student final sectioning)
  - getJenrlWeight
```
public double getJenrlWeight(Student student)
```
  - decJenrl
```
public void decJenrl(Student student)
```
    Decrement the number of joined enrollments (during student final sectioning)
  - getJenrl
```
public long getJenrl()
```
    Number of joined enrollments (during student final sectioning)
  - jenrl
```
public double jenrl()
```
  - priority
```
public double priority()
```
  - getNrStudents
```
public int getNrStudents()
```
  - getStudents
```
public Set<Student> getStudents()
```
  - getNrInstructors
```
public int getNrInstructors()
```
  - getInstructors
```
public Set<Student> getInstructors()
```
  - isHard
```
public boolean isHard()
```
    Description copied from class: Constraint
    
    Returns true if the constraint is hard. Only hard constraints are allowed to unassign a variable when there is a conflict with a value that is being assigned
    
    Overrides:
    
    isHard in class Constraint<Lecture,Placement>
  - isOverLimit
```
public boolean isOverLimit()
```
  - getName
```
public String getName()
```
    Description copied from class: Constraint
    
    Constraint's name -- for printing purposes
    
    Overrides:
    
    getName in class Constraint<Lecture,Placement>
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - areStudentConflictsHard
```
public boolean areStudentConflictsHard()
```
  - areStudentConflictsDistance
```
public boolean areStudentConflictsDistance()
```
  - areStudentConflictsCommitted
```
public boolean areStudentConflictsCommitted()
```
  - areStudentConflictsDistance
```
public boolean areStudentConflictsDistance(Placement value)
```
  - isOfTheSameProblem
```
public boolean isOfTheSameProblem()
```
  - weaken
```
public void weaken()
```
    Description copied from interface: WeakeningConstraint
    
    Weaken the constraint. This method is called if the constraint participates in an unassigned of a variable.
    
    Specified by:
    
    weaken in interface WeakeningConstraint<Lecture,Placement>
  - weaken
```
public void weaken(Placement value)
```
    Description copied from interface: WeakeningConstraint
    
    Weaken the constraint enough so that it can assign the given value.
    
    Specified by:
    
    weaken in interface WeakeningConstraint<Lecture,Placement>
  - isToBeIgnored
```
public boolean isToBeIgnored()
```
    Returns true if there is IgnoreStudentConflictsConstraint between the two lectures.

Class JenrlConstraint

Field Summary

Fields inherited from class net.sf.cpsolver.ifs.model.Constraint

Constructor Summary

Method Summary

Methods inherited from class net.sf.cpsolver.ifs.model.BinaryConstraint

Methods inherited from class net.sf.cpsolver.ifs.model.Constraint

Methods inherited from class java.lang.Object

Constructor Detail

JenrlConstraint

Method Detail

addVariable

computeConflicts

inConflict

isConsistent

unassigned

isInConflict

assigned

jenrl

isInConflict

incJenrl

getJenrlWeight

decJenrl

getJenrl

jenrl

priority

getNrStudents

getStudents

getNrInstructors

getInstructors

isHard

isOverLimit

getName

toString

areStudentConflictsHard

areStudentConflictsDistance

areStudentConflictsCommitted

areStudentConflictsDistance

isOfTheSameProblem

weaken

weaken

isToBeIgnored