jcifs-ng will be a proper choice for many users. 
There are a lot of SMB devices in the world.
Some of them only work with the old jcifs library.
If you want to support many SMB devices, CodeLibs jcifs library will be helpful.
For example, since [Fess](https://github.com/codelibs/fess) needs to support many SMB devices, it uses this library.

    private final boolean smb2;


    /**
     * Creates an {@link java.io.OutputStream} for writing bytes to a file on
     * an SMB server represented by the {@link jcifs.smb.SmbFile} parameter. See
     * {@link jcifs.smb.SmbFile} for a detailed description and examples of
     * the smb URL syntax.
     *
     * @param file
     *            An <code>SmbFile</code> specifying the file to write to
     * @throws SmbException

        this.useBatching = Config.getBoolean(p, "jcifs.smb.client.useBatching", false);
        this.useUnicode = Config.getBoolean(p, "jcifs.smb.client.useUnicode", true);
        this.useLargeReadWrite = Config.getBoolean(p, "jcifs.smb.client.useLargeReadWrite", true);
        this.forceUnicode = Config.getBoolean(p, "jcifs.smb.client.forceUnicode", false);
        this.signingPreferred = Config.getBoolean(p, "jcifs.smb.client.signingPreferred", false);

import jcifs.SmbTransportPool;
import jcifs.netbios.NameServiceClientImpl;
import jcifs.smb.BufferCacheImpl;
import jcifs.smb.CredentialsInternal;
import jcifs.smb.DfsImpl;
import jcifs.smb.Handler;
import jcifs.smb.NtlmPasswordAuthenticator;
import jcifs.smb.SIDCacheImpl;
import jcifs.smb.SmbFile;
import jcifs.smb.SmbNamedPipe;
import jcifs.smb.SmbTransportPoolImpl;


/**
 * @author mbechler
 *
 */

    /**
     * 
     * Property <tt>jcifs.smb.client.ipcSigningEnforced</tt> (boolean, default true)
     * 
     * @return whether to enforce SMB signing for IPC connections
     */
    boolean isIpcSigningEnforced ();


    /**
     * 
     * Property <tt>jcifs.smb.client.signingEnforced</tt> (boolean, default false)
     * 
     * @return whether to enforce SMB signing (for everything)
     */

            final Map<String, Object> metaDataMap = responseData.getMetaDataMap();
            if (responseData.getUrl().startsWith("smb:")) {
                final SID[] allowedSids = (SID[]) metaDataMap.get(SmbClient.SMB_ALLOWED_SID_ENTRIES);
                if (allowedSids != null) {
                    for (final SID sid : allowedSids) {

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.DirFileEntryEnumIteratorBase#getResults()
     */
    @Override
    protected FileEntry[] getResults () {
        return this.response.getResults();
    }


    /**
     * {@inheritDoc}
     * 
     * @throws CIFSException
     *
     * @see jcifs.smb.DirFileEntryEnumIteratorBase#fetchMore()
     */
    @Override

        Config.registerSmbURLHandler();

        try (SmbFile f = new SmbFile("smb://127.0.0.1/")) {
            Assert.assertEquals("smb://127.0.0.1/", f.toString());
        }
        try (SmbFile f = new SmbFile("smb://foo:b%40r@127.0.0.1/")) {
            Assert.assertEquals("smb://foo:******@127.0.0.1/", f.toString());
        }
    }

import jcifs.smb.NtStatus;
import jcifs.smb.NtlmNtHashAuthenticator;
import jcifs.smb.NtlmPasswordAuthentication;
import jcifs.smb.NtlmPasswordAuthenticator;
import jcifs.smb.NtlmUtil;
import jcifs.smb.SmbAuthException;
import jcifs.smb.SmbException;
import jcifs.smb.SmbFile;
import jcifs.smb.SmbSessionInternal;
import jcifs.smb.SmbTransportInternal;
import jcifs.smb.SmbTreeHandleInternal;


/**
 * 

     * resource is effectively it's parent. The root URL <code>smb://</code>
     * does not have a parent. In this case <code>smb://</code> is returned.
     *
     * @return The parent directory of this SMB resource or
     *         <code>smb://</code> if the resource refers to the root of the URL
     *         hierarchy which incidentally is also <code>smb://</code>.
     */