NullPointer when trying to get ContentInfo from VFS FileObject

Question

I'm successfully using VFS to download files from HTTP, SFTP, FTP, etc. I need to get the content type of the file and I've run into a strange thing that I'm not sure why is happening.

FileObject file = vfs.resolveFile(uri) ;
FileContent content = remote.getContent();

InputStream source = content.getInputStream();
ByteArrayOutputStream target = new ByteArrayOutputStream();
copy(source, target);

content.getSize(); // HACK: Prevents null-pointer in next line
String type = content.getContentInfo().getContentType();

If I remove the call to getSize, content.getContentInfo will return null. Why is this? Am I missing something?

What happens if you throw this line before and after the `getSize` call? `System.out.println(content.isOpen() ? "Open" : "Closed");` — durron597, Apr 30 '13 at 14:59
Looks like an [`issue`](http://mail-archives.apache.org/mod_mbox/commons-issues/201207.mbox/%3C1860309366.38128.1342042175019.JavaMail.jiratomcat@issues-vm%3E) — Sam R., Apr 30 '13 at 15:43
@AdamArold Think I tried with HTML, XML and PDF over HTTP. Might have tried over SFTP as well, can recheck at work. — Svish, May 01 '13 at 10:16
It seems that `getSize` has some side effect which is unhealthy for your app. In that case the problem is with the library. — Adam Arold, May 01 '13 at 12:15
@durron597 Tested now, and it reports 'Closed' both before and after the getSize call. — Svish, May 02 '13 at 07:48

score 1 · Accepted Answer · answered Jan 06 '15 at 00:03

1

As @Sam-Rad wrote, it is fixed in trunk (upcoming VFS 2.1):

https://issues.apache.org/jira/browse/VFS-427

answered Jan 06 '15 at 00:03

eckes

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NullPointer when trying to get ContentInfo from VFS FileObject

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