title: sorting strings in Java based on substrings
body: <p>I have a list of strings <strong>def123, abc999, zzz000, abc123, zzz111</strong>.
  I want the list sorted such that first three characters are sorted in ascendng order and next three in descending.
  So the output should be <strong>abc999, abc123, def123, zzz111,zzz000</strong>
  Is this possible?</p>