Groovy: How to write on a line on the same position on screen? (Windows)

Question

I want to show advance % in groovy , so I want to write on the same position, which means that instead of seeing:

1%
2%
3%
...

The user will see the figures changing in the same location. How do I do that? (I'm working on windows)

Answer 1

I do this frequently just using a carriage return without a line feed:

printf "%5d\r", loopval

Each time through your loop, printing will start over again at the beginning of the line.

It can get a tad messy if any other messages should print out while this is happening, especially if the other message contain newlines. But it's a cheap and dirty solution.

Answer 2

You can use jline that comes with Groovy:

(1..5).each {
  print "Done $it of 5"
  Thread.sleep( 1000 )
  print jline.ANSIBuffer.ANSICodes.left( 9999 )
}

So long as your console supports ANSI escape sequences, that should work...

PS: I used 9999 because (as it says in the documentation for left)

If n is greater or equal to the current cursor column, the cursor is moved to the first column