There are tools out there, Jumble for one, that perform analysis through branch coverage, by mutating your code to see if your test fails for all different permutations.
Directly from their website:
Jumble is a class level mutation
testing tool that works in conjunction
with JUnit. The purpose of mutation
testing is to provide a measure of the
effectiveness of test cases. A single
mutation is performed on the code to
be tested, the corresponding test
cases are then executed. If the
modified code fails the tests, then
this increases confidence in the
tests. Conversely, if the modified
code passes the tests this indicates a
testing deficiency.
