Does someone know/have experience in showing Java web application generated UI in Sharepoint? We have a Java web application and are evaluating the possibilities to embed Java-generated web UI into Sharepoint. I don't think Sharepoint supports Java portlets, but it might support consuming WSRP?
As previously mentioned, the SharePoint team released the WSRP toolkit a few months back. More details available here.
If that doesn't work out for you (I've never tried it so have no experience to share) depending on the UI requirements you can always use the simple route of the Page Viewer Web Part.
This essentially creates a mini-browser (I believe it uses an iFrame) within a SharePoint page. If you're portlet is simply a data entry/display method it may work out for you and it's definitely less work.