[jira] [Commented] (HADOOP-9590) Move to JDK7 improved APIs for file operations when available

["Steve Loughran (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/HADOOP-9590?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13663991#comment-13663991 ] 

Steve Loughran commented on HADOOP-9590:
----------------------------------------

Not so much "the supported platform" as "the minimum platform supported by Hadoop". This is something that could maybe be considered in the 2.2.+/3.x timeframe.

Note that currently you can't build Hadoop on Java7 on OS/X, see HADOOP-9350 for the specifics. Getting Hadoop to build and run reliably on Java7 is a prerequisite to this.

Maybe we should create two meta-JIRA's "build and run on Java7 everywhere" and only after that "adopt java-7 specific features".
                
> Move to JDK7 improved APIs for file operations when available
> -------------------------------------------------------------
>
>                 Key: HADOOP-9590
>                 URL: https://issues.apache.org/jira/browse/HADOOP-9590
>             Project: Hadoop Common
>          Issue Type: Improvement
>            Reporter: Ivan Mitic
>
> JDK6 does not have a complete support for local file system file operations. Specifically:
> - There is no symlink/hardlink APIs what forced Hadoop to defer to shell based tooling
> - No error information returned when File#mkdir/mkdirs or File#renameTo fails, making it unnecessary hard to troubleshoot some issues
> - File#canRead/canWrite/canExecute do not perform any access checks on Windows making APIs inconsistent with the Unix behavior
> - File#setReadable/setWritable/setExecutable do not change access rights on Windows making APIs inconsistent with the Unix behavior
> - File#length does not work as expected on symlinks on Windows
> - File#renameTo does not work as expected on symlinks on Windows
> All above resulted in Hadoop community having to fill in the gaps by providing equivalent native implementations or applying workarounds. 
> JDK7 addressed (as far as I know) all (or most) of the above problems, either thru the newly introduced [Files|http://docs.oracle.com/javase/7/docs/api/java/nio/file/Files.html] class or thru bug fixes.
> This is a tracking Jira to revisit above mediations once JDK7 becomes the supported platform by the Hadoop community. This work would allow significant portion of the native platform-dependent code to be replaced with Java equivalents what is goodness w.r.t. Hadoop cross-platform support. 

--
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