It looks like you have all the listeners listening on the same port. If the port is opened and used by one listener object, I am not sure you could use it for another listener object.

Without knowing exactly what you are trying to achieve, it's hard to tell, but I am guessing the design of your app can be improved. If you are going to use just one port, instead of maintaining an array of listeners, create a thread that listens onto the specific port and alerts the application whenever any data is received on that port.

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