JasperSoft Studio
In Preview, run report by clicking green arrow, if no errors the export menu will be enable, click the export button (disk image) and select "Export As Pdf"
To export a you need to fill the report to get the JasperPrint object.
Export single JasperPrint (single jrxml) to file
// 1. Create exporter instance
JRPdfExporter exporter = new JRPdfExporter();
// 2. Set exporter input document
exporter.setExporterInput(new SimpleExporterInput(jasperPrint)...