com.cloudant.sync.replication

Class QueuingExecutorCompletionService<Q,R>

java.lang.Object

java.util.concurrent.ExecutorCompletionService<R>

com.cloudant.sync.replication.QueuingExecutorCompletionService<Q,R>

Type Parameters:

Q - reQuest type

R - Response type

All Implemented Interfaces:

java.util.concurrent.CompletionService<R>

public abstract class QueuingExecutorCompletionService<Q,R>
extends java.util.concurrent.ExecutorCompletionService<R>

This class extends the ExecutorCompletionService using a Queue of requests to operate a policy of submitting a new request for execution after a previous request has completed. The number of concurrent requests allowed can be specified and that number of jobs will be submitted on construction after which the one complete, one submitted policy applies. This has the advantage of terminating submission of requests for execution if responses stop being retrieved from the CompletionService.

Constructor Summary

Constructors

Constructor and Description
QueuingExecutorCompletionService(java.util.concurrent.ExecutorService executorService, java.util.Queue<Q> requests, int concurrentRequests)

Method Summary

Modifier and Type	Method and Description
abstract R	executeRequest(Q request) Subclasses should override this method with the desired execution method, which will ultimately be wrapped in a Callable for submission to the ExecutorCompletionService.
boolean	hasRequestsOutstanding()
java.util.concurrent.Future<R>	poll()
java.util.concurrent.Future<R>	poll(long timeout, java.util.concurrent.TimeUnit unit)
java.util.concurrent.Future<R>	take()

Methods inherited from class java.util.concurrent.ExecutorCompletionService

submit, submit

Methods inherited from class java.lang.Object

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

Constructor Detail

QueuingExecutorCompletionService

public QueuingExecutorCompletionService(java.util.concurrent.ExecutorService executorService,
                                        java.util.Queue<Q> requests,
                                        int concurrentRequests)

Parameters:

executorService - the executor service to execute the requests

requests - the Queue of requests to execute

concurrentRequests - the number of concurrent requests

Method Detail

hasRequestsOutstanding

public boolean hasRequestsOutstanding()

Returns:

true if requests have been submitted that have not yet been retrieved from the CompletionService

poll

public java.util.concurrent.Future<R> poll()

Specified by:

poll in interface java.util.concurrent.CompletionService<R>

Overrides:

poll in class java.util.concurrent.ExecutorCompletionService<R>

poll

public java.util.concurrent.Future<R> poll(long timeout,
                                           java.util.concurrent.TimeUnit unit)
                                    throws java.lang.InterruptedException

Specified by:

poll in interface java.util.concurrent.CompletionService<R>

Overrides:

poll in class java.util.concurrent.ExecutorCompletionService<R>

Throws:

java.lang.InterruptedException

take

public java.util.concurrent.Future<R> take()
                                    throws java.lang.InterruptedException

Specified by:

take in interface java.util.concurrent.CompletionService<R>

Overrides:

take in class java.util.concurrent.ExecutorCompletionService<R>

Throws:

java.lang.InterruptedException

executeRequest

public abstract R executeRequest(Q request)

Subclasses should override this method with the desired execution method, which will ultimately be wrapped in a Callable for submission to the ExecutorCompletionService.

Parameters:

request -

Returns:

response