[VFS-726] getInputStream(int bufferSize) on SftpFileObject effectively ignores buffer size

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.4.1
• Fix Version/s: 2.5.0
• Flags: Important
• Assignee: Gary D. Gregory
• Reporter: Cornelius Höfig
• Created: 16/Aug/19 11:39
• Updated: 05/Nov/19 15:53
• Resolved: 19/Aug/19 22:08

Description

When calling getInputStream(int bufferSize) on an SftpFileObject

the callstack looks like this :

at java.io.BufferedInputStream.<init>(BufferedInputStream.java:199)
at java.io.BufferedInputStream.<init>(BufferedInputStream.java:183)
at org.apache.commons.vfs2.util.MonitorInputStream.<init>(MonitorInputStream.java:40)
at org.apache.commons.vfs2.provider.sftp.SftpFileObject$SftpInputStream.<init>(SftpFileObject.java:485)
at org.apache.commons.vfs2.provider.sftp.SftpFileObject.doGetInputStream(SftpFileObject.java:455)
at org.apache.commons.vfs2.provider.AbstractFileObject.getInputStream(AbstractFileObject.java:1175)
at org.apache.commons.vfs2.provider.DefaultFileContent.buildInputStream(DefaultFileContent.java:495)
at org.apache.commons.vfs2.provider.DefaultFileContent.getInputStream(DefaultFileContent.java:356)

The problem is that when initialising the BufferedInputstream it is done with the DEFAULT_BUFFER_SIZE of 8192.

The problem seems to be that in DefaultFileContent.buildInputStream(final Integer bufferSize) the it tries to get a raw InputStream and then wrap it into a FileContentInputStream but in reality the fileObject.getInputStream() in line 495 already returns a BufferedInputStream instead of a raw InputStream. It is effectively double buffered.

 

Issue Links

• relates to: VFS-704 Some providers wrap their input/output streams twice in a BufferedInputStream