### Question:
SnowflakeUtil { public static Snowflake getInstance() { if (snowflake == null) { synchronized (SnowflakeUtil.class) { if (snowflake == null) { snowflake = new Snowflake(WORKID); } } } return snowflake; } private  SnowflakeUtil(); static Snowflake getInstance();  }### Answer:
@Test public void test(){ Snowflake snowflake = SnowflakeUtil.getInstance(); }