All Known Implementing Classes:

AggregatingCalculationListener, ResultsListener
```
public interface CalculationListener
```
Listener that is notified when calculations are performed by a CalculationRunner.
It is guaranteed that the methods of a listener will only be invoked by a single thread at any time. It is not guaranteed to be the same thread invoking a listener each time. The calling code is synchronized to ensure that any changes in the listener state will be visible to every thread used to invoke the listener. Therefore listener implementations are not required to be thread safe.
A listener instance should not be used for multiple sets of calculations.

Method Summary

All Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method	Description
`void`	`calculationsComplete()`	Invoked when all calculations have completed.
`default void`	`calculationsStarted(List<CalculationTarget> targets, List<Column> columns)`	Invoked when the calculations start; guaranteed to be invoked before `resultReceived(CalculationTarget, CalculationResult)` and `calculationsComplete()`.
`void`	`resultReceived(CalculationTarget target, CalculationResult result)`	Invoked when a calculation completes.

- Method Detail
  - calculationsStarted
```
default void calculationsStarted(List<CalculationTarget> targets,
                                 List<Column> columns)
```
    Invoked when the calculations start; guaranteed to be invoked before resultReceived(CalculationTarget, CalculationResult) and calculationsComplete().
    
    Parameters:
    
    targets - the targets for which values are being calculated; these are often trades
    
    columns - the columns for which values are being calculated
  - resultReceived
```
void resultReceived(CalculationTarget target,
                    CalculationResult result)
```
    Invoked when a calculation completes.
    It is guaranteed that calculationsStarted(List, List) will be called before this method and that this method will never be called after calculationsComplete().
    It is possible that this method will never be called. This can happen if an empty list of targets is passed to the calculation runner.
    
    Parameters:
    
    target - the calculation target, such as a trade
    
    result - the result of the calculation
  - calculationsComplete
```
void calculationsComplete()
```
    Invoked when all calculations have completed.
    This is guaranteed to be called after all results have been passed to resultReceived(com.opengamma.strata.basics.CalculationTarget, com.opengamma.strata.calc.runner.CalculationResult).
    This method will be called immediately after calculationsStarted(List, List) and without any calls to resultReceived(CalculationTarget, CalculationResult) if there are no calculations to be performed. This can happen if an empty list of targets is passed to the calculation runner.

Interface CalculationListener

Method Summary

Method Detail

calculationsStarted

resultReceived

calculationsComplete