Bind report parameter to a sql output jasper report - jasper-reports

Question

I have an existing report which needs to modified a little. Suppose my report query is like
select name,currency,productcode from where name=?
Now this '?' value will come from a report parameter say countryName. That can be done using parameterized query not a problem.
Now what I need is this parameter countryName to get the data from another query like below
select name from countries
In short I want to bind the value of report parameter countryName to the output of the above query and also I want to put this query in report it self.
Using birt its very easy but I want to know is it possible with jasper?
P.S I'm novice in jasper report.
I have tried to give an small scenario to represent my issue. The actual report is much more that this and is very complex.
Any help would be highly appreciated!!

Answer 1

I give you an answer how this can be achieved without passing anything through the parameter map (even if I think the parameter map should be the preferred way, modify your standard module to support parameter map)
You say you will have combobox value with the country name, we need to make it static. (or have a static way to access it, "there can be only one")
Example class of your interface:
package com.your.package;
public class SelectCountryInterface {
private static JComboBox<String> selectCountry;
public static synchronized String getSelectedCountry(){
Object value = selectCountry.getSelectedItem();
if (value instanceof String){
return (String)value;
}
return "";
}
//...Here goes you code to instance and populate the combobox
}
In jasper report (.jrxml)
Define a parameter and set the defaultValueExpression to point at your static method in class, this way it will be initialized with the value that you are providing from your interface class.
<parameter name="country" class="java.lang.String" isForPrompting="false">
<defaultValueExpression><![CDATA[com.your.package.SelectCountryInterface.getSelectedCountry()]]> </defaultValueExpression>
</parameter>
Set the queryString to use your parameter
<queryString>
<![CDATA[select name,currency,productcode from where name=$P{country}]]>
</queryString>