[jira] [Commented] (MAPREDUCE-5020) Compile failure with JDK8

["Hadoop QA (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/MAPREDUCE-5020?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13583628#comment-13583628 ] 

Hadoop QA commented on MAPREDUCE-5020:
--------------------------------------

{color:red}-1 overall{color}.  Here are the results of testing the latest attachment 
  http://issues.apache.org/jira/secure/attachment/12570367/MAPREDUCE-5020.patch
  against trunk revision .

    {color:green}+1 @author{color}.  The patch does not contain any @author tags.

    {color:red}-1 tests included{color}.  The patch doesn't appear to include any new or modified tests.
                        Please justify why no new tests are needed for this patch.
                        Also please list what manual steps were performed to verify this patch.

    {color:green}+1 javac{color}.  The applied patch does not increase the total number of javac compiler warnings.

    {color:green}+1 javadoc{color}.  The javadoc tool did not generate any warning messages.

    {color:green}+1 eclipse:eclipse{color}.  The patch built with eclipse:eclipse.

    {color:green}+1 findbugs{color}.  The patch does not introduce any new Findbugs (version 1.3.9) warnings.

    {color:green}+1 release audit{color}.  The applied patch does not increase the total number of release audit warnings.

    {color:green}+1 core tests{color}.  The patch passed unit tests in hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core.

    {color:green}+1 contrib tests{color}.  The patch passed contrib unit tests.

Test results: https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/3354//testReport/
Console output: https://builds.apache.org/job/PreCommit-MAPREDUCE-Build/3354//console

This message is automatically generated.
                
> Compile failure with JDK8
> -------------------------
>
>                 Key: MAPREDUCE-5020
>                 URL: https://issues.apache.org/jira/browse/MAPREDUCE-5020
>             Project: Hadoop Map/Reduce
>          Issue Type: Bug
>          Components: client
>    Affects Versions: 2.0.3-alpha
>         Environment: java version "1.8.0-ea"
> Java(TM) SE Runtime Environment (build 1.8.0-ea-b36e)
> Java HotSpot(TM) Client VM (build 25.0-b04, mixed mode)
>            Reporter: Trevor Robinson
>            Assignee: Trevor Robinson
>              Labels: build-failure, jdk8
>         Attachments: MAPREDUCE-5020.patch
>
>
> Compiling {{org/apache/hadoop/mapreduce/lib/partition/InputSampler.java}} fails with the Java 8 preview compiler due to its stricter enforcement of JLS 15.12.2.6 (for [Java 5|http://docs.oracle.com/javase/specs/jls/se5.0/html/expressions.html#15.12.2.6] or [Java 7|http://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.12.2.6]), which demands that methods applicable via unchecked conversion have their return type erased:
> {noformat}
> [ERROR] hadoop-common/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/partition/InputSampler.java:[320,35] error: incompatible types: Object[] cannot be converted to K[]
> {noformat}
> {code}
>   @SuppressWarnings("unchecked") // getInputFormat, getOutputKeyComparator
>   public static <K,V> void writePartitionFile(Job job, Sampler<K,V> sampler) 
>       throws IOException, ClassNotFoundException, InterruptedException {
>     Configuration conf = job.getConfiguration();
>     final InputFormat inf = 
>         ReflectionUtils.newInstance(job.getInputFormatClass(), conf);
>     int numPartitions = job.getNumReduceTasks();
>     K[] samples = sampler.getSample(inf, job); // returns Object[] according to JLS
> {code}

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira