@Test public void testHeartbeat() throws Exception { Path file1 = new Path(filesDir + Path.SEPARATOR + "file1"); fs.create(file1).close(); // acquire lock on file1 FileLock lock1 = FileLock.tryLock(fs, file1, locksDir, "spout1"); Assert.assertNotNull(lock1); Assert.assertTrue(fs.exists(lock1.getLockFile())); ArrayList<String> lines = readTextFile(lock1.getLockFile()); Assert.assertEquals("heartbeats appear to be missing", 1, lines.size()); // hearbeat upon it lock1.heartbeat("1"); lock1.heartbeat("2"); lock1.heartbeat("3"); lines = readTextFile(lock1.getLockFile()); Assert.assertEquals("heartbeats appear to be missing", 4, lines.size()); lock1.heartbeat("4"); lock1.heartbeat("5"); lock1.heartbeat("6"); lines = readTextFile(lock1.getLockFile()); Assert.assertEquals("heartbeats appear to be missing", 7, lines.size()); lock1.release(); lines = readTextFile(lock1.getLockFile()); Assert.assertNull(lines); Assert.assertFalse(fs.exists(lock1.getLockFile())); }