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Change the connection port and ip adress. If you're trying to connect to your server from your own computer, check if you haven't already connected to the server in another instance.
Try changing the port in core-site.xml from 9000 to 9001 as it seems port 9000 doesn't work.
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java.net.BindException: Address already in use
at sun.nio.ch.Net.bind0(Native Method)