Rich Internet applications (RIAs) can use the Java Network Launch Protocol (JNLP) API to perform extensive operations on the user's environment. When launched by using JNLP, even unsigned RIAs can perform the following operations with the user's permission:
FileOpenService and
FileSaveService API to access the user's file system..ClipboardService API to access the shared system-wide clipboard.PrintService API to access printing functions.PersistenceService API to access persistence storage.DownloadService API to control how the RIA is downloaded and cached.DownloadServiceListener API to determine progress of the RIA's download.SingleInstanceService API to decide how to handle arguments when multiple instances of the RIA are launched.ExtendedService API to request permission to open certain files that have not been opened before.Check the JNLP API documentation to see the complete list of the functionality available to RIAs that are launched by using JNLP.