A cleaned-up and improved version of the jCIFS library
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README.md

jcifs-ng

A cleaned-up and improved version of the jCIFS library

Latest stable release:

<dependency>
    <groupId>eu.agno3.jcifs</groupId>
    <artifactId>jcifs-ng</artifactId>
    <version>2.1.0</version>
</dependency>

Latest maintenance release (will be discontinued after a couple of releaeses in the 2.1 series):

<dependency>
    <groupId>eu.agno3.jcifs</groupId>
    <artifactId>jcifs-ng</artifactId>
    <version>2.0.7</version>
</dependency>

Changes

  • SMB2 (2.02 protocol level) support, some SMB3 support
  • Remove global state
  • Allow per context configuration
  • Logging through SLF4J
  • Drop pre-java 1.7 support
  • Unify authentication subsystem, NTLMSSP/Kerberos support
  • Large ReadX/WriteX support
  • Streaming list operations
  • NtTransNotifyChange support
  • Google patches: various bugfixes, lastAccess support, retrying requests
  • A proper test suite
  • Various fixes

Migration

jcifs-ng 2.1

This release enables SMB2 support by default and contains some experimental SMB3.0 support.

Protocol levels negotitated can now be controlled with jcifs.smb.client.minVersion and jcifs.smb.client.maxVersion (this deprecates the jcifs.smb.client.enableSMB2 / jcifs.smb.client.disableSMB1 properties). Default min/max versions are SMB1 to SMB210.

This release deprecates server browsing (i.e. server/workgroup enumeration) and contains some breaking API changes regarding authentication.

jcifs-ng 2.0

This release features SMB2 support (2.02 protocol level), for now SMB2 support is only announced if configured jcifs.smb.client.enableSMB2 but may also be chosen if the server does not support SMB1 dialects.

Users are encouraged to enable it and test thoroughly.

jcifs-ng 1.6 (unreleased)

This release is not binary compatible and depending on your usage you will encounter source incompatibilities as well (mostly custom SmbNamedPipes or watch() but also if you use any APIs that should be considered internal).

Resource lifecycle improvements required some API breaks as well as non-trivial behavior changes that unfortunately in most cases require changes to user code. This however is deemed a necessary change to prevent certain bugs concerning idle timeouts. The original implementation simply did not know when it was okay to idle disconnect or whether there was still some resource in use that would be broken by that disconnect (e.g. a locked file would be magically unlocked by it). That behavior also introduced quite a number of potential race conditions resulting in errors.

For every file handle opened there is now an object which clearly controls it's lifetime (setting aside invalidation by connection errors), namely

  • SmbFileInput/OutputStream
  • SmbRandomAccessFile
  • SmbWatchHandle
  • SmbPipeHandle

Any of these objects now require that it is explicitly closed - all implement AutoCloseable and therefor can be managed using try-with-resources. If you used to close them through SmbFile.close() that will no longer have the desired effect.

Also SmbFile used to share file handles between different uses (e.g. if you opened multiple Input/OutputStreams) they would all share the same handle. That no longer is the case and doing so on a file opened non-shareable will now fail.

Failing to properly close them will result in the underlying session/connection no longer being disconnected by idle timeout as well as keeping the file and tree handle open on the server (and producing a warning when the session/connection is forcibly terminated).

If you want to take this one step further, there also is a strict mode in which keeping an SmbFile open will keep-alive it's tree handle. This has the benefit of preventing some delays for reestablishing rarely used tree handles, however it requires that all SmbFile instances are properly closed by the user after use.

This release also features more refactoring resulting in an API/implmentation split that should make it easier for users to decide what should be considered public and what internal API. New users are encourage to use SmbResources obtained through CIFSContext->get() instead of directly referencing SmbFile. The APIs in the jcifs package should be considered stable, everything else possibly unstable (although SmbFile won't be going away) and several implementation details have been hidden. If you encounter use cases that require the use of implementation classes or internal interfaces - please open an issue.

jcifs-ng 1.5

Global state removal/multi configuration support required some API breaks with regards to upstream jcifs. Methods now typically require that you pass a CIFSContext object which holds the context state, configuration and credentials. Various utility methods that were static before have been moved to services that can be obtained from such a context.

If you want to retain old behavior (global shared state and configuration through system properties) you may pass jcifs.context.SingletonContext.getInstance() for these context parameters. If a method had a NtlmPasswordAuthentication parameter replace it with

SingletonContext.getInstance().withCredentials(ntlmPasswordAuthentication)