cannot load sub-report after setting SUBREPORT_DIR > default value expression

i have create one report that contain subreport. everything goes fine before i set the default value expression at SUBREPORT_DIR. There is no problem during compilling but when i tried to view using iReport, it appear error filling print. And when i try to load it from jsp, it said error loading object caus开发者_C百科ed by : java.io.StreamcorruptedExecption : invalid stream header: 3C68746D.

It is parameter problem. Check the parameter, make sure it correct and match. check also the initial value. Also check the parameter variable in jsp wether it the same syntax in the report.