@Override
    public String onNameServerAddressChange(String namesrvAddress) {
        if (namesrvAddress != null) {
            if (!namesrvAddress.equals(this.nameSrvAddr)) {
                log.info("name server address changed, old=" + this.nameSrvAddr + ", new=" + namesrvAddress);
                this.updateNameServerAddressList(namesrvAddress);
                this.nameSrvAddr = namesrvAddress;
                return nameSrvAddr;
            }
        }
        return nameSrvAddr;
    }
@Test
    public void assertOnNameServerAddressChange() {
        assertEquals(defaultNsAddr, mqClientAPI.onNameServerAddressChange(defaultNsAddr));
    }