Problems casting from string to Double

[augarte]

Hi,

I've a field "pxf" that is a string but I want to cast to Double. I guess the easiest way for doing that is creating a variable. I have created a variable with the following expression:

Double.parseDouble($F{pxf})

It seems it is ok but when I execute the report I get the following error:

1. Cannot cast from double to Double
                value = (java.lang.Double)(Double.parseDouble(((java.lang.String)field_pxf.getValue()))); //$JR_EXPR_ID=8$
                        <------------------------------------------------------------------------------>
2. Cannot cast from double to Double
                value = (java.lang.Double)(Double.parseDouble(((java.lang.String)field_pxf.getOldValue()))); //$JR_EXPR_ID=8$
                        <--------------------------------------------------------------------------------->
3. Cannot cast from double to Double
                value = (java.lang.Double)(Double.parseDouble(((java.lang.String)field_pxf.getValue()))); //$JR_EXPR_ID=8$
                        <------------------------------------------------------------------------------>
3 errors

I have also tried changing the expression to this one:

new Double (${pxf})

But I also have an error with this one:

net.sf.jasperreports.engine.fill.JRExpressionEvalException: Error evaluating expression :
        Source text : new Double($F{pxf})

I have set the variable type to "java.lang.Double" and the type of the  TextField where I try to print the variable is also "java.lang.Double". I don't know how can I fix that. Any idea?

Thanks in advance,

Cheers, Aitor.

P.D. I attach the .jrxml file

[cbarlow3]

If I set my scripting language to JavaScript, I'm able to cast the String fields to Double variable using the parseFloat() function.   Actually, JavaScript is so forgiving on data types, that I also got it to work with just making the expression be "$F{doublestring}*1"  Just to be sure, I also defined a variable that keeps a sum of all the double values and displays in a summary.  jrxml pasted below, and screenshot of the report attached.  Good luck!

Carl

Code:

Post Edited by cbarlow3 at 10/27/2010 15:59

[svenn]

You are getting that error because parseDouble returns a double (primative) and not a Double which is a object. Though they are both double they are not exactly the same thing.

Use the follow which converts a String to a Double

Double.valueOf($F{pxf})

[augarte]

Thanks for your answers!!!

Double.parseDouble ($F{pxf}) is working!!! I only have one problem:

I use a xml file as datasource and the is an element which is empty. Casting this element gives me an error because it tries doing the following:

Double.valueOf (""). Do you know how can I solve that?

Thanks in advance!

Cheers,

Aitor

Post Edited by augarte at 10/28/2010 06:22

[mdahlman]

You'll have to decide what you want to do with null values. One possibility is converting them to 0. You could use an expression like this:

Double.parseDouble( ($F{pxf}==null) ? 0 : $F{pxf} )

If your field is a String you might also need to test for an empty string rather than just for a null object. The same ideas will apply.

Regards,
Matt