Showing posts from September, 2011

Linux rfcomm serial communication

Scan to discover Bluetooth device Pair with Bluetooth device Connect with SPP In one shell/terminal - pipe the input from the Bluetooth device to a file      less -f /dev/rfcomm0 then ctrl+F or      tail -f /dev/rfcomm0 or      cat /dev/rfcomm0 > datalog.txt In another shell/terminal - echo some command to the Bluetooth device      echo "8;" > /dev/rfcomm0 Quit the cat command Inspect the output      less datalog.txt

Windows Soft Link

mklink (a windows softlink)

Manifest classpath

Manifest classpath examples

Message Digest

MD5 throughput was ~15 GBytes/minute on a quad core Intel i5 @ 2.67GHz running Ubuntu Linux 10.04 and Java(TM) SE Runtime Environment (build 1.6.0_22-b04) Java HotSpot(TM) Server VM (build 17.1-b03, mixed mode) The throughput was the same whether the digest was computed from bytes on disk or memory. org.apache.commons.codec.digest.DigestUtils org.apache.commons.codec.binary.Hex From file String filename = "src/test/resources/somefile"; is = new FileInputStream(filename); assertEquals("bd6b1dc1ac767b018003572a767d2d0d", DigestUtils.md5Hex(is)); Pipe filter stream is = new DigestInputStream( new BufferedInputStream(new FileInputStream(filename)), MessageDigest.getInstance("MD5")); /* * Implementations using DigestInputStream would not need the byte handling as it would be just one filter in a pipe * that is being pumped for some other purpose. */ final byte[] buf = new byte[2048]; while (