IloCplex.Callback

java.lang.Object
- ilog.opl.IloCplex.Callback

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

IloCplex.ContinuousCallback, IloCplex.CrossoverCallback, IloCplex.MIPInfoCallback, IloCplex.NetworkCallback

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.opl.IloCplex.Aborter)

Method Summary

Methods
Modifier and Type	Method and Description
`protected void`	`abort()` Aborts current optimization.
`protected double`	`getCplexTime()` This method returns a time stamp, useful in measuring elapsed time in seconds.
`protected double`	`getDetTime()` This method returns a deterministic time stamp in ticks.
`protected double`	`getEndDetTime()` This method returns a deterministic time stamp specifying when the deterministic time limit will occur.
`protected double`	`getEndTime()` This method returns a time stamp specifying when the time limit will occur.
`protected IloEnv`	`getEnvImpl()`
`protected 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 double`	`getStartDetTime()` This method returns a deterministic time stamp specifying when the solving process was started.
`protected double`	`getStartTime()` This method returns a time stamp specifying when the solving process was started.
`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.
    
    Throws:
    
    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 IloModel getModel()
                     throws IloException
```
    Returns the model being solved when the invoking callback is called, that is the active model.
    
    Throws:
    
    IloException
    
    Returns:
    The model being solved when the invoking callback is called.
  - getCplexTime
```
protected double getCplexTime()
```
    This method returns a time stamp, useful in measuring elapsed time in seconds.
    
    To measure time spent between a starting point and ending point of an operation, take the result of this method at the starting point; take the result of this method at the end point; subtract the starting time stamp from the ending time stamp; the subtraction yields elapsed time in seconds.
    
    Whether the elapsed time measures wall clock time (also known as real time) or CPU time depends on the setting of the clock type parameter ClockType.
    
    The absolute value of the time stamp is not meaningful.
  - getDetTime
```
protected double getDetTime()
```
    This method returns a deterministic time stamp in ticks.
    
    To measure elapsed deterministic time in ticks between a starting point and ending point of an operation, take the deterministic time stamp at the starting point; take the deterministic time stamp at the ending point; subtract the starting deterministic time stamp from the ending deterministic time stamp.
    
    The absolute value of the deterministic time stamp is not meaningful.
  - getStartTime
```
protected double getStartTime()
```
    This method returns a time stamp specifying when the solving process was started. To compute elapsed time in seconds, subtract the result of getCplexTime from the result of this method. This computation yields either wall clock time (also known as real time) or CPU time, depending on the clock type set by the parameter ClockType. The absolute value of the time stamp is not meaningful.
  - getStartDetTime
```
protected double getStartDetTime()
```
    This method returns a deterministic time stamp specifying when the solving process was started. To compute elapsed time in ticks, subtract the result of getDetTime from the result of this method.
    
    The absolute value of the deterministic time stamp is not meaningful.
  - getEndTime
```
protected double getEndTime()
```
    This method returns a time stamp specifying when the time limit will occur. To compute remaining time in seconds, subtract the result of getCplexTime from the result of this method. This computation yields either wall clock time (also known as real time) or CPU time, depending on the clock type set by the parameter ClockType. The absolute value of the time stamp is not meaningful.
  - getEndDetTime
```
protected double getEndDetTime()
```
    This method returns a deterministic time stamp specifying when the deterministic time limit will occur. To compute remaining time in ticks, subtract the result of getDetTime from the result of this method.
    
    The absolute value of the deterministic time stamp is not meaningful.
  - 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.
  - getEnvImpl
```
protected IloEnv getEnvImpl()
```

Class IloCplex.Callback

Method Summary

Methods inherited from class java.lang.Object

Method Detail

main

abort

getModel

getCplexTime

getDetTime

getStartTime

getStartDetTime

getEndTime

getEndDetTime

getNrows

getNQCs

getNcols

getEnvImpl