Subreport of the jasper report displays blank, how do i solve this??

Question

i am creating a report which has subreport that is embeded in to the master report.
When i previee it works fine but when i use it on my code it doesa'nt, it only display balank page.
I could view the report individualy but not together.
please guide me
Thank you
Master Report
<subreport isUsingCache="true">
    <reportElement key="testingrpts_subreport1" x="21" y="72" width="517" height="100" isRemoveLineWhenBlank="true" isPrintInFirstWholeBand="true" isPrintWhenDetailOverflows="true"/>
    <connectionExpression><![CDATA[$P{REPORT_CONNECTION}]]></connectionExpression>
    <subreportExpression class="java.lang.String"><![CDATA["C:\\Documents and Settings\\uthays\\My Documents\\NetBeansProjects\\POSYS\\POSYS-war\\web\\testingrpts_subreport1.jasper"]]></subreportExpression>
   </subreport>

Answer 1

hi i have improved the report but not yet solved it.
i now got parameters that passes value. i understand the logic but when i try it, it doeant work
<subreport>
                    <reportElement x="16" y="72" width="525" height="109"/>
                    <subreportParameter name="CURRENT_Order">
                         <subreportParameterExpression><![CDATA[$F{poheader_id}]]></subreportParameterExpression>
                    </subreportParameter>
                    <connectionExpression><![CDATA[$P{REPORT_CONNECTION}]]></connectionExpression>
                    <subreportExpression class="java.lang.String"><![CDATA[$P{SUBREPORT_DIR} + "newsub.jasper"]]></subreportExpression>
               </subreport>then i am using this in my java
fillParams.put("pSubReportName", input);
       param.put("CURRENT_Order",new Integer(poheaderDataProvider.getValue("id").toString()));but still i could only list one at a time
if any1 got any clue let me know please, thank you