Eliminating feedback in Java Sound?

Question

I have completed a Java program that is for video-conferencing. It reads and writes from the mic/speaker of a network camera that includes two-way audio. This network camera does not have feedback reduction built in, so I must do it myself.

I can manually measure the latency, and use volume adjustment to cut out the mic to eliminate the feedback in that way, but do you have a better idea?

Ideally, my program would eliminate the feedback, without having to cut out unwanted parts. Suppose I am in a two-way conversation. I don't want to miss what the other side is saying, simply because I am talking at the same moment, especially because there is significant latency.

Can you recommend a library, or at least a strategy, for eliminating feedback?

Additionally, I would like any tips you may have on eliminating the fuzz that occurs even if the room is completely quiet. Again, I can use volume detection to mute when the room is silent, but then the fuzz is audible as soon as someone starts talking. (Or, do you think I should ask about that separately?)