### Question:
ConnectionManager { public static String maskPassword(String password) { return password == null ? "" : StringUtils.repeat("*", password.length()); } private  ConnectionManager();   ConnectionManager(DataSourceFactory factory, Ticker ticker, long sleepIntervalNanos); static ConnectionManager getInstance(); Connection getConnection(String server, String jdbcUrl, Properties connectionConfiguration, boolean isPoolEnabled, Properties poolConfiguration, String qualifier); static String maskPassword(String password);  }### Answer:
@Test public void testMaskPassword () { assertEquals("********", ConnectionManager.maskPassword("12345678")); assertEquals("", ConnectionManager.maskPassword("")); assertEquals("", ConnectionManager.maskPassword(null)); }