VMware Tanzu GemFire Native C++ Reference 10.2.7
apache::geode::client::ResultCollector Class Referenceabstract

Defines the interface for a container that gathers results from function execution. More...

#include <ResultCollector.hpp>

Inherited by apache::geode::client::DefaultResultCollector.

Public Member Functions

virtual void addResult (const std::shared_ptr< Cacheable > &resultOfSingleExecution)=0
 Adds a single function execution result to the ResultCollector. More...
 
virtual void clearResults ()=0
 Geode will invoke this method before re-executing function (in case of Function Execution HA) This is to clear the previous execution results from the result collector. More...
 
virtual void endResults ()=0
 Geode will invoke this method when function execution has completed and all results for the execution have been obtained and added to the ResultCollector}. More...
 
virtual std::shared_ptr< CacheableVectorgetResult (std::chrono::milliseconds timeout=DEFAULT_QUERY_RESPONSE_TIMEOUT)=0
 Returns the result of function execution, potentially blocking until all the results are available. More...
 
 ResultCollector ()=default
 public methods More...
 

Detailed Description

Defines the interface for a container that gathers results from function execution.


Geode provides a default implementation for ResultCollector. Applications can choose to implement their own custom ResultCollector. A custom ResultCollector facilitates result sorting or aggregation. Aggregation functions like sum, minimum, maximum and average can also be applied to the result using a custom ResultCollector. Example:

auto rc = FunctionService::onRegion(region)
                                     .withArgs(args)
                                     .withFilter(keySet)
                                     .withCollector(new
MyCustomResultCollector())
                                     .execute(Function);
 //Application can do something else here before retrieving the result
auto functionResult = rc.getResult();
See also
FunctionService

Constructor & Destructor Documentation

◆ ResultCollector()

apache::geode::client::ResultCollector::ResultCollector ( )
default

public methods

Member Function Documentation

◆ addResult()

virtual void apache::geode::client::ResultCollector::addResult ( const std::shared_ptr< Cacheable > &  resultOfSingleExecution)
pure virtual

Adds a single function execution result to the ResultCollector.

Parameters
resultOfSingleExecutionsingle function execution result to add
Since
5.8LA

◆ clearResults()

virtual void apache::geode::client::ResultCollector::clearResults ( )
pure virtual

Geode will invoke this method before re-executing function (in case of Function Execution HA) This is to clear the previous execution results from the result collector.

Since
6.5

◆ endResults()

virtual void apache::geode::client::ResultCollector::endResults ( )
pure virtual

Geode will invoke this method when function execution has completed and all results for the execution have been obtained and added to the ResultCollector}.

◆ getResult()

virtual std::shared_ptr< CacheableVector > apache::geode::client::ResultCollector::getResult ( std::chrono::milliseconds  timeout = DEFAULT_QUERY_RESPONSE_TIMEOUT)
pure virtual

Returns the result of function execution, potentially blocking until all the results are available.

If geode sendException is called then ResultCollector.getResult will not throw exception but will have exception UserFunctionExecutionException as a part of results received.

Parameters
timeoutif result is not ready within this time, exception will be thrown
Returns
the result
Exceptions
FunctionExceptionif result retrieval fails
See also
UserFunctionExecutionException

Apache Geode C++ Cache API Documentation