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Some code in those posts show how to get a cell's contents given its row and column.
Change that code to go row by row from the first row to the last row
and for each row to get each cell from...

Have you tried asking Google?
I found these:
https://gist.github.com/mansueli/1806103bf9873adaba0d
https://stackoverflow.com/questions/11347535/javafx-tableview-copy-to-clipboard

Also posted...