When you install JReport Designer, which by default is located in C:\JReport\Designer, JReport Result Viewer Bean is also installed at the same time. After installation, you will have the main components in <install_root> as below:
Notes:
For example, when you use the Result Viewer Bean to export to mail, you should add mail.jar and activation.jar with a valid path to your class path. When you use the Result Viewer Bean to export to XML, you should add resource.jar with a valid path to your class path. When you use JReport Engine Bean to export to Excel, you should add poiHSSF_151.jar with a valid path to your class path, and when you use JReport Engine Bean to export to PDF, you should add Itext.zip with a valid path to your class path.