ilog.cplex
Class IloCplex.Callback

java.lang.Object
  |
  +--ilog.cplex.IloCplex.Callback

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

IloCplex.ContinuousCallback, IloCplex.CrossoverCallback, IloCplex.MIPCallback, IloCplex.NetworkCallback, IloCplex.PresolveCallback

Enclosing class:

IloCplex

public abstract static class IloCplex.Callback

extends java.lang.Object

implements java.lang.Cloneable

The callback base class.

This class defines the common interface available to all callback classes. A callback is an object with a method main implemented by the user. This method is called by the IloCplex algorithm at specific points during the optimization. For each of these points, an extension of IloCplex.Callback is provided. To implement and use a particular callback, the following steps must be carried out:

• Select the callback class corresponding to the callback to be implemented, and create an extension of that class.
• Implement method main for this extension. When doing so, you may use all of the methods defined in the callback class and its base classes.
• If the default implementation of the method clone is not adequate and the callback is to be used for parallel optimization, this method also needs to be implemented by the user. Recall that the default clone method performs a shallow copy, so typically a user implementation would perform a deep copy for objects that should be local to threads or use the synchronize keyword where synchronization is required.
• Create an instance of the user-written callback class and pass it to IloCplex with the method IloCplex.use.

The next time a solution method is executed on the IloCplex object for which the callback has been set, the method main of the callback will be called each time the corresponding point in the optimization algorithm is reached.

The methods of this class are protected to make sure they are used only to derive a user-written callback class or to implement the main method in it.

See Also:

IloCplex.use(ilog.cplex.IloCplex.Callback)

Method Summary

protected void	abort() Aborts current optimization.
protected ilog.concert.IloModel	getModel() Returns the model being solved when the invoking callback is called, that is the active model.
protected int	getNcols() Returns the number of columns of the matrix representation of the active model being solved when the invoking callback is called.
protected int	getNQCs() Returns the number of quadratic constraints in the active model being solved when the invoking callback is called.
protected int	getNrows() Returns the number of rows of the matrix representation of the active model being solved when the invoking callback is called.
protected abstract void	main() The method to be implemented by user callback classes.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

main

protected abstract void main()
                      throws IloException

The method to be implemented by user callback classes.

IloException

abort

protected void abort()

Aborts current optimization. This method can be called from a user-written implementation of a main method to instruct the invoking IloCplex optimizer to abort the current optimization.

getModel

protected ilog.concert.IloModel getModel()
                                  throws IloException

Returns the model being solved when the invoking callback is called, that is the active model.

Returns:

The model being solved when the invoking callback is called.

IloException

getNrows

protected int getNrows()

Returns the number of rows of the matrix representation of the active model being solved when the invoking callback is called.

Returns:

The number of rows of the matrix representation of the active model.

getNQCs

protected int getNQCs()

Returns the number of quadratic constraints in the active model being solved when the invoking callback is called.

Returns:

The number of quadratic constraints in the active model.

getNcols

protected int getNcols()

Returns the number of columns of the matrix representation of the active model being solved when the invoking callback is called.

Returns:

The number of columns of the matrix representation of the active model.