[Java Client] Fix JavaDoc for closeAsync: remove documented exception…

[michaeljmarshall]

… that isn't thrown

Motivation

Fix JavaDoc on the PulsarClient interface.

Changes

• Switch throws to return as the method does not actually throw the checked exception

Testing

No tests needed, as this change just updates the documentation to align with the code.

Documentation

This is fixing documentation. The website does not need to be updated.

[michaeljmarshall]

/pulsarbot run-failure-checks

[michaeljmarshall]

/pulsarbot run-failure-checks

[eolivelli]

Lgtm

We do not have a good way to document possibile error outcomes of CompletareFuture.
This is a general problem for libraries that use this mechanism.

I am not sure if we should document anyway the fact that some kind of error may occur

[michaeljmarshall]

Lgtm

We do not have a good way to document possibile error outcomes of CompletareFuture.
This is a general problem for libraries that use this mechanism.

I am not sure if we should document anyway the fact that some kind of error may occur

@eolivelli - this is a good point. We could choose to list some of the expected exceptions here. However, there won't be any compile time checks to ensure that implementations of this interface only throw documented exceptions.

Since this is a generic problem that extends even beyond Pulsar, I don't think we should try to solve it in this PR. I copied the updated comment from another client interface:

pulsar/pulsar-client-api/src/main/java/org/apache/pulsar/client/api/Reader.java

Lines 78 to 83 in e2bc52d

	/**
	* Asynchronously close the reader and stop the broker to push more messages.
	*
	* @return a future that can be used to track the completion of the operation
	*/
	CompletableFuture<Void> closeAsync();

[michaeljmarshall]

@gaoran10 @315157973 @aahmed-se @codelipenghui - PTAL