Question

How do I convert a double value with 10 digits for e.g 9.01236789E9 into a string 9012367890 without terminating any of its digits ?

I tried 9.01236789E9 * Math.pow(10,9) but the result is still double “9.01236789E18”

Answer 1

While 10 digits should be preservable with no problems, if you’re interested in the actual digits used, you should probably be using BigDecimal instead.

If you really want to format a double without using scientific notation, you should be able to just use NumberFormat to do that or (as of Java 6) the simple string formatting APIs:

import java.text.*;

public class Test
{
    public static void main(String[] args)
    {
        double value = 9.01236789E9;
        String text = String.format("%.0f", value);
        System.out.println(text); // 9012367890

        NumberFormat format = NumberFormat.getNumberInstance();
        format.setMaximumFractionDigits(0);
        format.setGroupingUsed(false);
        System.out.println(format.format(value)); // 9012367890
    }
}