[
https://issues.apache.org/jira/browse/VFS-683?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16693981#comment-16693981
]
Otto Fowler commented on VFS-683:
---------------------------------
{code:java}
/**
* Returns an input stream for reading the file's content.
* <p>
* There may only be a single input or output stream open for the file at any
time.
*
* @return An input stream to read the file's content from. The input stream is
buffered, so there is no need to
* wrap it in a {@code BufferedInputStream}.
* @throws FileSystemException If the file does not exist, or is being read, or
is being written, or on error
* opening the stream.
*/
InputStream getInputStream() throws FileSystemException;
{code}
Just from looking through things, It doesn't seem correct to have two threads
going through here.
The Resource.getBytes() call explicitly CLOSES the stream. So, it isn't
thread safe for two readers if there is only ever one stream from the same
object
> Thread safety issue in VFSClassLoader - NullPointerException thrown
> -------------------------------------------------------------------
>
> Key: VFS-683
> URL: https://issues.apache.org/jira/browse/VFS-683
> Project: Commons VFS
> Issue Type: Bug
> Affects Versions: 2.2
> Reporter: Daryl Odnert
> Priority: Major
>
> In my application, I have two instances of the {{VFSClassLoader}}, each of
> which is being used in a distinct thread. Both {{VFSClassLoader}} instances
> refer to the same compressed file resource described by a {{FileObject}} that
> is passed to the class loader's constructor. Intermittently, the application
> throws an exception with the stack trace shown below. So, there seems to be
> either a race condition in the code or an undocumented assumption here. If it
> is unsupported for two {{VFSClassLoader}} instances to refer to the same
> resource (file), then that assumption should be documented. But if that is
> not the case, then there is a race condition bug in the implementation.
> {noformat}
> 43789 WARN {} c.a.e.u.PreferredPathClassLoader - While loading class
> org.apache.hive.jdbc.HiveDatabaseMetaData, rethrowing unexpected
> java.lang.NullPointerException: Inflater has been closed
> java.lang.NullPointerException: Inflater has been closed
> at java.util.zip.Inflater.ensureOpen(Inflater.java:389)
> at java.util.zip.Inflater.inflate(Inflater.java:257)
> at java.util.zip.InflaterInputStream.read(InflaterInputStream.java:152)
> at java.io.BufferedInputStream.read1(BufferedInputStream.java:284)
> at java.io.BufferedInputStream.read(BufferedInputStream.java:345)
> at
> org.apache.commons.vfs2.util.MonitorInputStream.read(MonitorInputStream.java:91)
> at org.apache.commons.vfs2.FileUtil.getContent(FileUtil.java:47)
> at org.apache.commons.vfs2.impl.Resource.getBytes(Resource.java:102)
> at
> org.apache.commons.vfs2.impl.VFSClassLoader.defineClass(VFSClassLoader.java:179)
> at
> org.apache.commons.vfs2.impl.VFSClassLoader.findClass(VFSClassLoader.java:150)
> at
> com.atscale.engine.utils.PreferredPathClassLoader.findClass(PreferredPathClassLoader.scala:54)
> {noformat}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
