We run the script that uses this functionality embedded in a java application. I noticed now that the first time the code runs after a cold start. This log message appears. 

java.nio.file.FileSystemNotFoundException: Provider "wrap" not installed
at java.nio.file.Paths.get(Paths.java:147)
at org.basex.util.Prop.homePath(Prop.java:142)
at org.basex.util.Prop.<clinit>(Prop.java:96)
at org.basex.core.StaticOptions.<clinit>(StaticOptions.java:20)
at org.basex.core.Context.<init>(Context.java:77)
at org.basex.core.Context.<init>(Context.java:69)
at se.kb.mimer.util.xquery.XQueryClient.extractPackageFilesData(XQueryClient.java:16)
....

The script still produces the expected output. I guess that this is a handled exception inside BaseX that get printed out to the log with INFO level. Am i right? 

Regards,
Johan

On Mon Jan 26 2015 at 2:24:41 PM Christian Grün <christian.gruen@gmail.com> wrote:
Hi Johan,

> Just wanted to report back that it works really well.

Glad to hear it works.

> It is about 50% slower
> than running the md5 command on the command line of my mac.

My final solution is close to the one you proposed [1]: I decided to
use a little buffer as well, because it was faster than calling
md.update() for each single byte.

Using nio channels gives us better performance:

    String path = ...
    RandomAccessFile raf = new RandomAccessFile(path, "r");
    FileChannel ch = raf.getChannel();
    ByteBuffer buf = ByteBuffer.allocate(IO.BLOCKSIZE);
    final MessageDigest md = MessageDigest.getInstance("md5");
    do {
      final int n = ch.read(buf);
      if(n == -1) break;
      md.update(buf.array(), 0, n);
      buf.flip();
    } while(true);
    System.out.println(Token.string(Token.hex(md.digest(), true)));

But I am not sure how smoothly this would integrate in our remaining
streaming architecture, as we are also streaming main-memory objects.
I'll keep it in mind, though.

Cheers,
Christian

[1] https://github.com/BaseXdb/basex/blob/master/basex-core/src/main/java/org/basex/query/func/hash/HashFn.java