Java - truncate string from left with formatter flag

Question

I have a string, say:

String s = \"0123456789\";

I want to pad it with a formatter. I can do this two ways:

String.format(\         


        

Answer 1

The - flag is for justification and doesn't seem to have anything to do with truncation.

The . is used for "precision", which apparently translates to truncation for string arguments.

I don't think format strings supports truncating from the left. You'll have to resort to

String.format("[%.5s]", s.length() > 5 ? s.substring(s.length()-5) : s);

Answer 2

You could also use method for manipulating Strings

substring(startindex, endIndex)

Returns a string object that starts a the specified index an goes to, but doesn't include, the end index.

And also could try to use StringBuilder class.

Answer 3

I hope this is what you need:

System.out.println("'" + String.format("%-5.5s", "") + "'");
System.out.println("'" + String.format("%-5.5s", "123") + "'");
System.out.println("'" + String.format("%-5.5s", "12345") + "'");
System.out.println("'" + String.format("%-5.5s", "1234567890.....") + "'");

output length is always 5:

'     ' - filled with 5 spaces
'123  ' filled with 2 spaces after
'12345' - equals
'12345' - truncated

in addition:

System.out.println("'" + String.format("%5.5s", "123") + "'");

output:

'  123' filled with 2 spaces before