commands in java to clear the screen

Question

What command in Java will let you clear the console in a command-line application?

Please clarify. What screen? The console? – Matt Ball Feb 03 '11 at 15:55 — Matt Ball, Feb 03 '11 at 15:55

score 18 · Answer 1 · answered Mar 15 '13 at 19:04

I think what the OP wants is to clear the screen and move the cursor to the home position. For that try:

        final String ANSI_CLS = "\u001b[2J";
        final String ANSI_HOME = "\u001b[H";
        System.out.print(ANSI_CLS + ANSI_HOME);
        System.out.flush();

Andrew White · Answer 2 · 2011-02-03T16:37:28.927

8

It depends on your console but if it supports ANSI escape sequences, then try this..

final static String ESC = "\033[";
System.out.print(ESC + "2J");

edited Feb 03 '11 at 16:37

answered Feb 03 '11 at 15:59

Andrew White

52,720
19
113
137

1

Something like this is probably your best bet, as I don't think there's a real Java solution (+1) – Sean Patrick Floyd Feb 03 '11 at 16:01
You don't need flush for System.out. – Anonymous Feb 03 '11 at 16:10
@wardedmocha: this would only work on an ANSI terminal emulator. It won't work on a vanilla Windows command prompt. DOS used to have ANSI.SYS, but on modern Windows systems it only works for DOS (I mean actual 20-year old DOS, not just CLI) applications. – thkala Feb 03 '11 at 16:16

score 3 · Answer 3 · answered Sep 29 '16 at 08:13

3

clearing for bash that is working for me:

System.out.print(String.format("\033[H\033[2J"));

answered Sep 29 '16 at 08:13

Alex

31
1

score 3 · Answer 4 · answered Feb 28 '11 at 16:51

3

Run this sample program: it demonstrates how to clear the console using an escape sequence and reposition the cursor to position X=1, Y=1.

I tested it on several Linux terminals. Don't know, if it works under Windows.
Perhaps you can tell me ;)

Read this article about escape sequences.

import java.io.*;

public class Main {

public static final char ESC = 27;

public static void main(String[] args)
        throws Exception {
    Console c = System.console();
    if (c == null) {
        System.err.println("no console");
        System.exit(1);
    }

    // clear screen only the first time
    c.writer().print(ESC + "[2J");
    c.flush();
    Thread.sleep(200);

    for (int i = 0; i < 100; ++i) {
        // reposition the cursor to 1|1
        c.writer().print(ESC + "[1;1H");
        c.flush();

        c.writer().println("hello " + i);
        c.flush();

        Thread.sleep(200);
    }
}

}

answered Feb 28 '11 at 16:51

java.is.for.desktop

10,748
12
69
103

I liked the script. I would to know if is there a way to put the text of the console into a variable before clearing the console, and later restore the console back to the state it was before ? Probably doing something like `buffer = System.out; ` `System.out.print(ESC+"[1;1H"); ` `System.out.flush(); ` `System.out.println("Lorem ispum ....");` `System.out.print(ESC+"[1;1H"); ` `System.out.flush(); ` `System.out.println(buffer);` – maan81 Aug 16 '12 at 15:07
Sorry, didn't know how to do multi-line comment. – maan81 Aug 16 '12 at 15:07
@maan81 Sadly, there is no way to "store" and "restore" System.out. It's just a stream. Java's console capabilities are *very* limited. – java.is.for.desktop Sep 06 '12 at 22:00

score 2 · Answer 5 · answered Sep 09 '17 at 18:32

2

If none of the above solutions works for you( as in my case ), try this solution:

new ProcessBuilder("cmd", "/c", "cls").inheritIO().start().waitFor();

I'm using Windows 8 and this solution worked for me. Hope it does to you as well. :)

answered Sep 09 '17 at 18:32

Kirankumar Ambati

535
4
10

score 2 · Answer 6 · edited Jun 20 '20 at 09:12

Clearing a screen generally requires sending special control sequences specific to the screen/terminal that your application is running under. Options:

If you know you will always running under a specific terminal and can find the proper control sequences to clear the screen for that terminal, just output those sequences. If you tell us the screen, we may be able to tell you the sequence (its likely somewhat ANSI/VT100/VT220 -compatible).
Externally ensure your app is always run in a desired terminal, e.g. a script to start your app starts the app in the desired terminal. Then output the necessary character sequence to clear the screen.
Take control of the terminal by using a terminal emulation library, i.e. you app is now a windowing app that creates a terminal window screen for the user to use. You then control what terminal you are emulating and will know what control sequences are needed.
Use a terminal library (e.g. like the historic curses library) that detects the terminal and provides an uniform interface to its features. See this question:

What's a good Java, curses-like, library for terminal applications?
Fake it by writing a bunch of lines to the screen.

score 1 · Answer 7 · answered Feb 03 '11 at 16:30

1

There is always the obvious (and kludgy)..

int numRowsInConsole = 60;
for (int ii=0; ii<numRowsInConsole; ii++) {
    // scroll down one line
    System.out.println("");
}

answered Feb 03 '11 at 16:30

Andrew Thompson

168,117
40
217
433

Or, simply call `System.out.println()`. – lupchiazoem Jan 18 '19 at 13:06

score 0 · Answer 8 · edited Feb 25 '15 at 17:00

0

System.out.println("Hello!");

prints the specified string and then moves the cursor to the next line.

System.out.print("Hello!");

prints the specified string and leaves the cursor immediately after that string.

To solve the problem, identified above, of the cursor being on the second line of the console, use print instead of println.

edited Feb 25 '15 at 17:00

Edd

3,724
3
26
33

answered Feb 25 '15 at 16:56

YYZ Teacher

1
1

score 0 · Answer 9 · answered May 25 '16 at 13:48

0

I did this in BlueJ and it worked perfectly: Try System.out.print("\f");

answered May 25 '16 at 13:48

Lori

161
1
3

score 0 · Answer 10 · answered Feb 15 '17 at 17:36

To my knowledge Windows 10's Command Window cmd.exe does not natively support ANSI ESC sequences, despite the rumors. To have the:

final String ANSI_CLS = "\u001b[2J";
System.out.print(ANSI_CLS);

method work you need a command line emulator that supports ANSI, such as ConEmu64.

score -1 · Answer 11 · answered May 04 '13 at 01:50

-1

There are two very simple ways to solve this, the first is the brute force option:

for (int i=1; i<=10; i++)
    System.out.println("\n");

The problem with this however is that it only pseudo clears the screen, you can scroll up to see the data, but don't fear, there is another way!

System.out.println("\f");

Voila! That should do the trick, although your cursor will be situated on the second line of the console after the screen is cleared.

answered May 04 '13 at 01:50

JFakult

327
1
2
16

1

What if the console is larger than ten lines in length? – Jakob Weisblat May 06 '13 at 21:03
2

Add several lines more – diegoaguilar Sep 14 '13 at 00:29

commands in java to clear the screen

11 Answers11

Linked

Related