On 27 Sep, 15:11, eric.steigerw...@va.gov wrote:

I presume that you define mrate somewhere as String too. If so, there
is NO way the error is where you say it is...
Working backwards logically:
1) your error message "it returns an error saying that it expects a
double, and found a string" means that you are trying to assign string
to variable defined as double. The ONLY place where I can see you
doing that is on line mrate =
show_student_awards.getString("monthly_rate"); mrate here is not
defined, but I presume it is a string.
2) that means your mrate is defined as double.
problem solved...

Please always copy/paste errors and exceptions.
It also helps to create an SSCCE* that others can
use to compare the code and any errors.

* <http://www.physci.org/codes/sscce.html>

Here is an example of an SSCCE.

<sscce>
import java.text.DecimalFormat;

class TestDecimalFormat {
 public static void main(String[] args) {
   DecimalFormat df = new DecimalFormat("0.00");
   String mrate = "4987.56";
   double dollar = Double.parseDouble(mrate);
   //double dollar2 = df.format(dollar);
   String dollar2 = df.format(dollar);
   System.out.println("Your bill is:  $" + dollar2);
 }
}
</sscce>

I'll leave it at that, but note that it is far better
to use the inbuilt power of Java to to some things,
and formatting currency is one of them.  

Look into NumberFormat.getCurrencyInstance(Locale)
Sun pays its engineers big bucks to figure these
things out for us.

HTH

DecimalFormat.format eats a double and produces a String.  You are
assuming it produce a double.