Lack { public void claim(String resource) throws LackException { ResultSet result = statements.acquire(resource, owner); if (!result.wasApplied()) { renewIfOwned(resource, result); } } Lack(LackConfig lackConfig, String owner); void acquire(String resource); void claim(String resource); void renew(String resource); void release(String resource); void stop();  }
@Test public void claimTwice() throws LackException { lack.claim(resource); lack.claim(resource); }