ResultBoundedCompletionService (Apache HBase 1.4.11 API)

java.lang.Object
- org.apache.hadoop.hbase.client.ResultBoundedCompletionService<V>

```
@InterfaceAudience.Private
public class ResultBoundedCompletionService<V>
extends Object
```
A completion service for the RpcRetryingCallerFactory. Keeps the list of the futures, and allows to cancel them all. This means as well that it can be used for a small set of tasks only.
Implementation is not Thread safe. CompletedTasks is implemented as a queue, the entry is added based on the time order. I.e, when the first task completes (whether it is a success or failure), it is added as a first entry in the queue, the next completed task is added as a second entry in the queue, ... When iterating through the queue, we know it is based on time order. If the first completed task succeeds, it is returned. If it is failure, the iteration goes on until it finds a success.

Constructor Summary

Constructors
Constructor and Description
`ResultBoundedCompletionService(RpcRetryingCallerFactory retryingCallerFactory, Executor executor, int maxTasks)`

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`cancelAll()`
`org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V>`	`poll(long timeout, TimeUnit unit)` Poll for the first completed task whether it is a success or execution exception.
`org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V>`	`pollForFirstSuccessfullyCompletedTask(long timeout, TimeUnit unit, int startIndex, int endIndex)` Poll for the first successfully completed task whose completed order is in startIndex, endIndex(exclusive) range
`void`	`submit(RetryingCallable<V> task, int callTimeout, int id)`
`org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V>`	`take()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ResultBoundedCompletionService

public ResultBoundedCompletionService(RpcRetryingCallerFactory retryingCallerFactory,
                              Executor executor,
                              int maxTasks)

Method Detail

submit

public void submit(RetryingCallable<V> task,
          int callTimeout,
          int id)

take

public org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V> take()
                                                                                     throws InterruptedException

Throws:: InterruptedException

poll

public org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V> poll(long timeout,
                                                                                   TimeUnit unit)
                                                                                     throws InterruptedException

Poll for the first completed task whether it is a success or execution exception.

Parameters:: timeout - - time to wait before it times out; unit - - time unit for timeout
Throws:: InterruptedException

pollForFirstSuccessfullyCompletedTask

public org.apache.hadoop.hbase.client.ResultBoundedCompletionService.QueueingFuture<V> pollForFirstSuccessfullyCompletedTask(long timeout,
                                                                                                                    TimeUnit unit,
                                                                                                                    int startIndex,
                                                                                                                    int endIndex)
                                                                                                                      throws InterruptedException,
                                                                                                                             CancellationException,
                                                                                                                             ExecutionException

Poll for the first successfully completed task whose completed order is in startIndex, endIndex(exclusive) range

Parameters:: timeout - - time to wait before it times out; unit - - time unit for timeout; startIndex - - start index, starting from 0, inclusive; endIndex - - end index, exclusive
Returns:: If within timeout time, there is no successfully completed task, return null; If all tasks get execution exception, it will throw out the last execution exception, otherwise return the first successfully completed task's result.
Throws:: InterruptedException; CancellationException; ExecutionException

cancelAll
```
public void cancelAll()
```

Class ResultBoundedCompletionService<V>

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ResultBoundedCompletionService

Method Detail

submit

take

poll

pollForFirstSuccessfullyCompletedTask

cancelAll