[
https://issues.apache.org/jira/browse/HAMA-378?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13025568#comment-13025568
]
ChiaHung Lin commented on HAMA-378:
-----------------------------------
The jar file exists on the groom server, but the file to be unpacked in the
path is not a correct one.
>From what has been discovered, it looks like when executing
>findContainingJar() in BSPJob, my_class.getClassLoader() would be different
>from what has been proposed in RunJar, in which the context class loader is
>set to URLClassLoader. Also, the jar file in command e.g. `hama jar
>path/to/eaxmple.jar` is added to classpath (if what perceived is correct). But
>in the findContainingJar function, the context loader is not the one proposed
>i.e. URLClassLoader; therefore, url.getProtocol() only returns `file' instead
>of `jar', resulting the execution of findContaingJar function returns null.
>Thus, bsp.jar is not set in configuration.
This is just what is discovered, but it might be a red herring and a further
investigation may be required.
> Lost connection to BSP Master [host/ip:port]. Retrying...
> -----------------------------------------------------------
>
> Key: HAMA-378
> URL: https://issues.apache.org/jira/browse/HAMA-378
> Project: Hama
> Issue Type: Improvement
> Components: bsp
> Reporter: ChiaHung Lin
> Priority: Minor
>
> When submitting a job, at the server side the GroomServer reports message
> Lost connection to BSP Master [host/ip:port]. Retrying...
> java.lang.NullPointerException
> This seems because the script hama only includes jar files (such as
> hama-0.3.0-examples.jar) located under basedir, the same folder as build.xml.
> Also, a quick check shows that when submitting a job, the ClassLader used is
> sun.misc.Launcher$AppClassLoader, instead of java.net.URLClassLoader. This
> might not be the root cause, but a further investigation may be required.
--
This message is automatically generated by JIRA.
For more information on JIRA, see: http://www.atlassian.com/software/jira
