Package org.apache.geode.cache.execute
Interface ResultSender<T>
public interface ResultSender<T>
Provides methods to send results back to the ResultCollector. A ResultSender adds the ability for
an execute method to send a single result back, or break its result into multiple pieces and send
each piece back to the calling thread's
ResultCollector. For each result sent using this
method, ResultCollector.addResult(org.apache.geode.distributed.DistributedMember, Object)
is called, making that result available to the calling thread immediately.
Example:
execute(FunctionContext context){
ResultSender rs = context.getResultSender();
int lastResult = -1;
for(int i=0;i< 10; i++) {
rs.sendResult(i);
}
rs.lastResult(lastResult);
}
Application can receive the results as they are sent using ResultSender in the above for loop.
It is very important to send a last result as it informs ResultCollector
to stop waiting for the result.
- Since:
- GemFire 6.0
- See Also:
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Method Summary
Modifier and TypeMethodDescriptionvoidlastResult(T lastResult) Sends a result back to the FunctionService calling thread and invokesResultCollector.addResult(org.apache.geode.distributed.DistributedMember, Object)and thenResultCollector.endResults()if it is the last instance of the Function to report results.voidSends an Exception back to the FunctionService calling thread.voidsendResult(T oneResult) Sends a result back to the FunctionService calling thread and invokesResultCollector.addResult(org.apache.geode.distributed.DistributedMember, Object).
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Method Details
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sendResult
Sends a result back to the FunctionService calling thread and invokesResultCollector.addResult(org.apache.geode.distributed.DistributedMember, Object).- Parameters:
oneResult- the result to be sent
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lastResult
Sends a result back to the FunctionService calling thread and invokesResultCollector.addResult(org.apache.geode.distributed.DistributedMember, Object)and thenResultCollector.endResults()if it is the last instance of the Function to report results. The ResultCollector will keep waiting for results until it receives last result. Therefore, it is very important to use this method to indicate end of function execution.- Parameters:
lastResult- the result to be sent- Throws:
IllegalStateException- if called more than once- See Also:
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sendException
Sends an Exception back to the FunctionService calling thread. sendException adds exception to ResultCollector as a result. If sendException is called thenResultCollector.getResult()will not throw exception but will have exception as a part of results received. Calling sendException will act as a lastResult.- Parameters:
t- theThrowableto be sent- Since:
- GemFire 6.3
- See Also:
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