MqttConnectOptions setting serverURIs is invalid

I want to try MqttConnect Options to set up server URIs to connect to multiple mosquitto servers. The settings don't seem to work.

This is the parameter value i set .
`MqttClient client = new MqttClient(”tcp://192.168.1.57:1883“, clientId, new MemoryPersistence());
MqttConnectOptions options = new MqttConnectOptions();
options.setUserName(userName);
options.setPassword(passWord.toCharArray());
options.setServerURIs(new String[]{"tcp://192.168.1.57:1883","tcp://192.168.1.37:1883"});`

node1：192.168.1.57
node2：192.168.1.37
They're all working properly.