Set System.setOut(); to Command Prompt

Question

I want to set output stream to the Command prompt like this:

Process p = Runtime.getRuntime()
              .exec("C:\\Windows\\System32\\cmd.exe /c start cls");
System.setOut(new PrintStream(p.getOutputStream()));

but it is not working, why ?

See http://stackoverflow.com/questions/4157303/how-to-execute-cmd-commands-via-java (the answers below the accepted answer) — ddmps, Apr 21 '13 at 17:12
but that does not execute command on cmd... so thats not acceptable. — Akhilesh Dhar Dubey, Apr 21 '13 at 17:26

score 0 · Answer 1 · answered Apr 21 '13 at 17:02

0

By default, PrintStreams will not flush contents written to them automatically. This means that data you write to it will not be immediately sent to the stream it wraps around. However, if you construct the PrintStream using new PrintStream(p.getOutputStream(), true), it will automatically flush when any of the println methods are invoked, a byte array is written or a newline is written. This way, anything you write to it will be immediately accessible to the process.

See http://docs.oracle.com/javase/7/docs/api/java/io/PrintStream.html

answered Apr 21 '13 at 17:02

TheSuccessor

124
7

This is not the problem here. – ddmps Apr 21 '13 at 17:11
ok i have done this `new PrintStream(p.getOutputStream(), true)` but still not getting message on cmd, why? – Akhilesh Dhar Dubey Apr 21 '13 at 17:13

Set System.setOut(); to Command Prompt

1 Answers1