You did not search hard enough.
The Processing website has resources (tutorials, references and examples) as well.
I would start with reading the text file and extracting a line as a string.
Check out the data tutorial and take a look at the related references.
Then decide how you want to send the data.
Check out the serial library and related references.
Fist thing that comes to mind is:
loadStrings()
serial.write()
You can write an entire string (check out the serial library) and receive it with the Arduino, parse it and convert the data back to integers (in this case). There are other ways to do this as well.
Do you already have Arduino code to receive this? You will have to send the data from Processing in a format that it will understand.
And your journey begins…
:)