public MapConfig setBackupCount(final int backupCount) {
        this.backupCount = checkBackupCount(backupCount, asyncBackupCount);
        return this;
    }
@Test
    public void testSetBackupCount() {
        assertEquals(0, new MapConfig().setBackupCount(0).getBackupCount());
        assertEquals(1, new MapConfig().setBackupCount(1).getBackupCount());
        assertEquals(2, new MapConfig().setBackupCount(2).getBackupCount());
        assertEquals(3, new MapConfig().setBackupCount(3).getBackupCount());
    }