CODEWITHSUNDEEP
javaconsole
Dave Brock
Dave Brock

Reputation: 387

Reading already-written text from console

I feel silly asking this but: how can I read a string from a console that is not input but has already been written to the console?

For instance, if I print a line to the console how can I read it after the fact? I know this is atypical.

Upvotes: 2

Views: 542

Answers (2)

Santhosh Kumar Tekuri
Santhosh Kumar Tekuri

Reputation: 3020

Replace both System.in and System.out with your own streams and try to create a pipe between System.in and System.out;

I am not sure that, whether it works or not;

Upvotes: 1

David Z
David Z

Reputation: 131600

Except in certain special circumstances, you can't, as Brad pointed out in the comments. As a justification, consider that when you send some text to the console (via standard output or standard error) to be printed, there's no guarantee that the text actually will be printed. Perhaps the user has redirected that output stream to /dev/null, in which case the text is gone for good. Or perhaps the text has scrolled out of view.

Basically, don't count on ever being able to access something that was sent to the console for output. If you need it, keep a copy in your program. And if you're trying to get at something that another program sent to the console, you need to use some sort of different arrangement like shared memory, sockets, or a fifo pipe.

Upvotes: 2

Related Questions