[
https://issues.apache.org/jira/browse/FLINK-18982?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17180414#comment-17180414
]
Benchao Li commented on FLINK-18982:
------------------------------------
Hi [~lemonjing], thanks for your contribution. AFAIK, the {{InputFormat}} is a
old interface, and will be replaced with new source api introduced by FLIP-27.
> InputFormat should remove unnecessary override methods
> ------------------------------------------------------
>
> Key: FLINK-18982
> URL: https://issues.apache.org/jira/browse/FLINK-18982
> Project: Flink
> Issue Type: Improvement
> Components: API / Core
> Affects Versions: 1.11.1
> Reporter: Ryan Tao
> Priority: Major
> Labels: pull-request-available
>
> _InputFormat_ has inherited from _InputSplitSource_. Based on basic Java
> knowledge, these two methods do not need to be written here, which may easily
> lead to ambiguity and duplicated.
> And the behavior of these two methods should belong to _InputSplitSource_
> instead of _InputFormat. (about split)_
> InputFormat:
> {code:java}
> public interface InputFormat<OT, T extends InputSplit> extends
> InputSplitSource<T>, Serializable {
> ...
> @Override
> T[] createInputSplits(int minNumSplits) throws IOException;
> @Override
> InputSplitAssigner getInputSplitAssigner(T[] inputSplits);
> ...
> }
> {code}
> InputSplitSource:
> {code:java}
> public interface InputSplitSource<T extends InputSplit> extends Serializable {
> T[] createInputSplits(int minNumSplits) throws Exception;
> InputSplitAssigner getInputSplitAssigner(T[] inputSplits);
> }{code}
> As for the reason, watching the commit history, we can find that these two
> methods appeared in _InputFormat_ before _InputSplitSource_. Later, they were
> taken to InputSplitSource separately, but they were not removed in
> _InputFormat_.
> Another point is that the _InputSplitSource throws an Exception_, as it
> should be. (Subclasses of InputFormat throw specific exception.)
> And the duplicated _InputFormat extends Serializable_.
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
