@Test
public void error() throws IOException, InterruptedException {

    SynchronizingSelfLog.error("test for SynchronizingSelfLog error situation");
    SynchronizingSelfLog.flush();
    File log = customFileLog("sync.log");
    List<String> logs = FileUtils.readLines(log);
    assertTrue(logs.toString(), logs.get(0).contains("[ERROR]"));
    assertTrue(logs.toString(),
        logs.get(0).contains("test for SynchronizingSelfLog error situation"));
}