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[SPARK-16877][BUILD] Add rules for preventing to use Java annotations…
… (Deprecated and Override) ## What changes were proposed in this pull request? This PR adds both rules for preventing to use `Deprecated` and `Override`. - Java's `Override` It seems Scala compiler just ignores this. Apparently, `override` modifier is only mandatory for " that override some other **concrete member definition** in a parent class" but not for for **incomplete member definition** (such as ones from trait or abstract), see (http://www.scala-lang.org/files/archive/spec/2.11/05-classes-and-objects.html#override) For a simple example, - Normal class - needs `override` modifier ```bash scala> class A { def say = {}} defined class A scala> class B extends A { def say = {}} <console>:8: error: overriding method say in class A of type => Unit; method say needs `override' modifier class B extends A { def say = {}} ^ ``` - Trait - does not need `override` modifier ```bash scala> trait A { def say } defined trait A scala> class B extends A { def say = {}} defined class B ``` To cut this short, this case below is possible, ```bash scala> class B extends A { | Override | def say = {} | } defined class B ``` we can write `Override` annotation (meaning nothing) which might confuse engineers that Java's annotation is working fine. It might be great if we prevent those potential confusion. - Java's `Deprecated` When `Deprecated` is used, it seems Scala compiler recognises this correctly but it seems we use Scala one `deprecated` across codebase. ## How was this patch tested? Manually tested, by inserting both `Override` and `Deprecated`. This will shows the error messages as below: ```bash Scalastyle checks failed at following occurrences: [error] ... : deprecated should be used instead of java.lang.Deprecated. ``` ```basg Scalastyle checks failed at following occurrences: [error] ... : override modifier should be used instead of java.lang.Override. ``` Author: hyukjinkwon <[email protected]> Closes apache#14490 from HyukjinKwon/SPARK-16877.
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