\b Formatting number with a pattern?

Question

I am trying to format a number according to the given format by the user. For eg: if the given number is
1234 and the given pattern is ###.# then my output should be 123.4 Now this is a simple pattern . The input pattern could be even like this ###,##,##.##.

Answer 1

The DecimalFormat won't change the value of what you give it, just format the value. One way to do what you want is to convert your number to a StringBuffer, then just add a decimal point where ever you want. This won't give you a great deal of flexability, but will solve the problem that you've given.
long dval = 123456;
StringBuffer sb = new StringBuffer(String.valueOf(dval));
sb = sb.insert(sb.length()-2, '.');
System.out.println(sb.toString());This code can easily be modified to be turned into a method that will take the value and the number of digits after the decimal that will return a String (or double or long) with the new value.